IE40294L - Preparation of vinyl chloride polymers - Google Patents

Description

4 o :i 'J \ i This invention relates to a process for the preparation of vinyl chloride polymers, especially transparent high impact strength and weather-resistant vinyl chloride polymers, by the cmulHion polymerization of vinyl chloride, either alone or together with at least one othor monomer copolymerizable therewith, in the presence of a preformed acrylic ester copolymer.

It i3 known (Belgian Patent No. 770011) to produce vinyl chloride polymers by the emulsion polymerization of vinyl chloride in the presence of 2 to 1036 by weight of a performed 2-ethyl hexyl acrylatc polymer. In comparison with vinyl chloride polymers produced by other known processes, these vinyl chloride polymers have increased impact strength and better transparency and are suitable for the production of translucent products; however, products produced therefrom exhibit too much haze (as defined hereinafter) for use as transparent products. If higher transparency is required, either the concentration or the particle diameter of the preformed 2-ethyl hexyl acrylate polymer must be 4020J reduced. Both these steps, however, reduce the impact strength of the resulting vinyl chloride polymers.

In another known process, a preformed copolymer consisting of 65 to 95% by weight of units derived from acrylic ester and 5 35 to 5% by weight of units derived from a-methyl styrene is used in the emulsion polymerization of vinyl chloride. Although the resulting vinyl chloride polymer has transparency which is enhanced by comparison with that of a polymer produced by other known processes, a polymer having high impact strength is not 10 obtained unless a relatively large amount of preformed copolymer is used. • The present invention provides a process for preparing a vinyl chloride polymer .which process comprises aqueous emulsion polymerizing monomelic material consisting of vinyl chloride and, 15 optionally, at least pne other monomer copolymerizable therewith, in the presence of ^ water-soluble initiator, an emulsifier and a dispersed preformed polymer, which preformed polymer consists of at least one copolymer consisting of (i) units derived from at least one acrylic ester, (ii) units derived from at least one 20 polyfunctional monomer having at least two non-conjugated ethylenic double bonds and at least one unsubstituted or substituted allylic end group containing one of the said double bonds and, optionally, (iii) units derived from a-methyl styrene.

In a first embodiment of the process of the present invention, 25 (a) at least 8096 by weight of the said monomeric material is vinyl chloride, (b) the said preformed polymer consists of at least one polymer consisting as a percentage by weight of the total weight of units (i), (ii) and (iii), of from 55 to 94.7% of units - 3 - 10 294 derived from at least one acrylic ester containing from 3 to 18 | carbon atoms ih the ester group from lO to O.3% of units derived from the said at least one polyfunctional monomer and from 35 to 5% by weight of vnits derived from a-methyl styrene, 5 (c) the said preformed polymer has a mean particle diameter of from 30 to 150 nn, preferably from 40 to 120 nm as determined by soap titration, and (d) the said preformed polymer is used in an amount such that from 4 to 2CTX, preferably from 5 to 10%, by weight of tho lO said vinyl chloride polymer consists of polymeric material derived from the said units derived from the said at least one acrylic ester.

In this first embodiment of the process of the present invention, the said preformed polymer preferably consists of at 15 loast one copolymer consisting, as a percentage by weight of the total weight of units (i). (ii) and (iii), of from 6.5 to 84.5% of units derived from the said at least one acrylic ester containing from 3 to 18, advantageously from 4 to 8, carbon atoms in the ester group, from 5 to 0.5% of units derived from the said at 20 least one polyfunctional monomer and from 30 to 15% of units derived from u-methyl styrene.

In a second embodiment of the process of the present invention, (a) at least 80% by weight of the said monomeric material 25 is vinyl chloride, (b) the said preformed polymer consists of at least one copolymer consisting, as a percentage by weight of the total weight of units (i), (ii) and (iii), of from 90 to 99.7% of units derived from at least one acrylj_ ester containing from 3 to 16 - 4 - 4 0 2 0 j carbon atoms in the cater group and from lO to 0.3% of units derived from tl»«* suitl at IimhI oiio polyl niu-l ionu I monomer, (c) The said preformed polymer has a mean particle diameter of from 30 to 150 nm, preferably from 40 to 120 nm, as determined 5 by soap titration, and (d) the said preformed polymer is used in an amount such that from 4 to 20% preferably from 5 to 10%, by weight of the said vinyl chloride polymer consists of units derived from the said at least one acrylic ester. lO In this second embodiment of the process of the present invention, the said preformed polymer preferably consists of at least one copolymer consisting, as a percentage by weight of the total weight of units (i), (ii) and (iii), of from 95 to 99.5% of units derived from at least one acrylic ester containing from 15 3 to 16, advantageously from 4 to 8, carbon atoms in the ester group and from 5 to O.5% of units derived from the said at least ono polyfunctional monomer.

In any proccss of the present invention the preformed polymer may contain units derived from just one acrylic ester or from a 20 plurality of different acrylic esters. However, a particularly preferred preformed polymer for use in the first embodiment of the process of the present invention is a copolymer consisting of units derived from two different acrylic esters, units derived from a said polyfunctional monomer and, units derived from a-25 methyl styrene and a particularly preferred preformed polymer for use in the second embodiment of the process of the present invention is a copolymer consisting of units derived from two different acrylic esters and units derived from a polyfunctional monomer. - 5 - ■10 2 9 4 Examples of acrylic esters from which the units (i) of the preformed polymer may be derived are propyl, isopropyl, butyl, isobutyl, hexyl, 2-ethyl hexyl, lauryl and myristyl acrylate and, if the preformed polymer contains units (iii) derived from a-5 methyl styrene, stearyl acrylate. Preferably, at least 90?6 of by weight of the units derived from the said at least one acrylic ester are units derived from 2-ethyl hexyl acrylate.

Examples of types of polyfunctional monomer from which the units (ii) of the-preformed polymer may be derived are mono-allyl lO and monomcthallyl esters of unsaturated mono-, di- and poly- carboxylic acids; diesters of unsaturated or saturated dicarboxy-lic acids, of cyanuric acid and of phosphoric acid; di-, tri- and totra-allyl and di-, tri- and tetramethallyl esters of saturated and unsaturated polycarboxylic acids, and of cyanuric acid and 15 of phosphoric acid; and poly-allyl (e.g. di-allyl) ethers of |x>lyhydric alcohol and polyallyl acetals. Specific examples of such polyfunctional monomers are allyl acrylate, allyl methacry-lato, allyl crotonate, allyl cinnamate, methallyl acrylate, methallyl methacrylate, monoallyl maleate, monoallyl fumarate, 20 diallyl oxalate, dimethallyl oxalate, diallyl glutarate, diallyl adipate, diallyl phthalate, diallyl terephthalate, tetra-allyl pyromellitate, diallyl maleate, dimethallyl maleate, diallyl fumarate, diallyl isocyanurate, triallyl cyanurate, triallyl phosphate, trimethylol propane, diallyl ether, trimethylol 25 propane diallyl ether monomethacrylate and tetra-allyl oxyethane.

The preformed polymer employed in the process of the present invention may be prepared by aqueous emulsion polymerization in the presence of a water-soluble initiator and an emulsifier, and the* emulsifier preferably consists of at least one salt of at - 6 - 40204 least one fatty acid containing fifom 12 to 18 carbon atoms, proforrod salts being the alkali and ammonium salts oC lauric acid, myristic acid, oleic acid, coconut oil acid, palmitic acid and stearic acid, coconut oil acid, palmitic acid and stearic acid. 5 Such an emulsifier advantageously is used in an amount of from 2 to 12% by weight based on the weight of the said at least one acrylic ester.

The mean particle diameter of the preformed polymer, which can be determined in a known manner, is dependent upon the emul-lO sion polymerization conditions employed for example, upon the amount of emulsifier used, and upon the manner of combining the monomers an The preformed polymer may be prepared by a polymerization reaction conducted in any of the following ways:- (a) all of the polyfunctional monomer is mixed with all of 20 tho acrylic ester and, if employed, the u-methyl styrene, in the reaction zone before the start of polymerization, or (b) all of the acrylic ester (and, if employed, the ci-methyl styrene), but only some,or even none of the polyfunctional monomer, is present in the reaction zone before the start of 25 polymerization, the latter being added during the reaction, or (c) only some of the acrylic ester (and, if employed, the A preferred copolymer dispersion containing particles having lO a relatively large mean particle diameter may be prepared by polymerization in the presence of a preformed latex of an acrylic ester homopolymer or copolymer, in which case the polymerization conditions arr so selected that the initially present polymer particles continue to grow without formation of new particles. Ir> Tho moan particle diumetor of the preformed polymer can be determined by various methods, for example, by light scatter measurements, by means of a disc centrifuge or by electron microscopy. In the latter case, however, there is a risk that the size of the polymer particles under investigation will change 20 so much durin.-l il K 5 where d denotes the mean particle diameter in nm of the polymer and E denotes the amount of grams of emulsifier required to cover one gram of the polymer with a monomolecular layer of emulsifier applies to titration with Mersolat K 30.

The process of the present invention for the polymerization lO of the said monomeric material is preferably carried out at a o temperature of from 50 to 70 C, with the preformed polymer in the form of a dispersion. The amount of preformed polymer employed depends on the polymerization temperature, the particle size of the preformed polymer and on the nature of the acrylic ester(s) 15 used in the preparation of the preformed polymer, this amount being such that preferably from 4 to 20%, more preferably from 5 to 10% by weight of the vinyl chloride polymer consists of polymeric material containing units derived from acrylic ester(s). The actual amount employed is so chosen that the vinyl chloride 20 polymer produced has desired properties. High transparency can be achieved by the use of any amount of preformed polymer lying within the specified preferred range. Generally, the use of a preformed polymer having a low content of units derived from acrylic ester provides vinyl chloride polymer having a moderate 25 impact strength, high softening temperature and high stiffness. An increase in the content of units derived from acrylic ester generally provides an increase in the impact strength and a - 9 - 4 0 2 0 <1 decrease in the stiffness of the vinyl chloride polymer. Those versed in the art will readily be able to select by experiment lln* combination of projM'rl ies nwnaary to provide n vinyl ohlo-rlilt* |M>lynwr suitable for ust? in a particlar application. Suit-5 able copolymerizable monomers include, in particular a-olefins, for example, ethylene, propylene and 1-butylene; unsaturated carboxylic acid esters such as esters of carboxylic acids with vinyl alcohol, for example, vinyl acetate, vinyl propionate, vinyl laurate and vinyl stearate, esters of acrylic acid with lO alcohols having 1—18 carbon atoms and diosters of maleic and fumaric acids with alcohols having 1—12 carbon atoms; and unsaturated ethers such as alkyl vinyl ethers, for example, methyl, ethyl, butyl, isobutyl, lauryl, cetyl and stearyl vinyl ether and methyl and ethyl isopropenyl ethers. In the case of a-olefins 15 fcfltimonomeric material may consist of from 80 to 97% by weight thereof of vinyl chloride and 20 to 3% by weight thereof of the u-olefin or unsaturated carboxylic acid ester; in the case of unsaturated ethers, the monomoric material may consist of from 85 to 99% by weight thereof of vinyl chloride and from 15 to 1% 20 by weight thereof of the unsaturated ether.

The emulsifier used for polymerization of the said monomeric material will usually be an anion-active emulsifier selected from, for example, a carboxylic acid salt, an alkyl sulphate, an alkyl sulphonate or an alkyl aryl sulphonate. Preferably, the emulsi-25 fier is at least one salt of at least one fatty acid containing 12—18 carbon atoms, for example, an alkali or ammonium salt of lauric acid, myristic acid, oleic acid, coconut oil acid, palmitic acid or stearic acid. Such an emulsifier is advantageously used in an amount of from 0.05 to 1% based on the weight of the mono- - 10 - meric material.

Die initiator used for polymerization of the said monomeric material may be a water-soluble free radical former e.g.a peroxide, persulphate, azo-compound or redox compound. Such an 5 initiator is advantageously used in an amount of from 0.05 to 0.5% by weight based on the weight of the monomeric material.

Polymerization of the said monomeric material may be carried out in the presence of a polymerization chain length controller, for example, a mercaptan or a saturated or unsaturated halogena-IO ted hydrocarbon. The amount of controller used depends upon its type and the required K-value of the vinyl chloride polymer product. Specific exampleajof the chain length controller are do-dccyl mercaptan, preferably used in an amount of from 0.01 to 0.2% by weight based on the weight of vinyl chloride, and tri-15 chloroethylene, 1,2-dichloroethylene and brexnoform, each preferably used in an amount of from 0.1 to 5% by weight based on the weight of vinyl chloride. Preferably, the type and amount of controller used is so chosen that the vinyl chloride polymer product has a K value of from 60 to 75. 20 Hie process of the present invention is preferably carried out using a pressure vessel which allows thorough mixing, for example, a pressure vessel equipped with an agitator, 4n aqueous dispersion of the preformed polymer, together with the initiator emulsifier and any controller being placed in the vessel and 25 the monomeric material consisting of vinyl chloride and any I other monomer copolymerizable therewith then being added to the vessel and polymerized therein.

The polymerization of the said monomeric material can be carried out at a pressure of from 65 to 99%, preferably of from - 11 - 75 to 9956, of the saturation pressure of the monomeric material at the temperature of polymerization. The monomeric vinyl chloride is partly in the gaseous state, partly dissolved in the aqueous phase and partly adsorbed in the polymer that has already 5 been formed;however, it should not be present in the liquid state per so during the polymerization reaction. Ihe desired pressure can be maintained by a continuous or substantially continuous supply of vinyl chloride as it is consumed during the polymerization reaction. This replenishment of vinyl chloride may, for lO example, be effected by connecting the polymerization vessel to a reservoir in which monomeric vinyl chloride —if necessary together with non-volatile polymerization inhibitor—is kept at such a temperature that the vapour pressure of the vinyl chloride in tin- rosnrvoir is nqua 1 to tho partial vapour pressure of the lr» vinyl chloride in tho polymerization vessel. Alternatively, the vinyl chloride may be continuously pumped in liquid form to the polymerization vessel; in a preferred embodiment, liquid vinyl chloride is introduced into the polymerization vessel in batches so small that tho pressure in the vessel remains substantially 20 constant, i.o. fluctuates in practice by less than 0.2 atmosphere about tho desired value. As a result of the pressure in the polymerization vessel being below the saturated pressure of tho monomeric material, the liquid vinyl chloride added is immediately vaporized on arrival in tho vessel before taking 25 part in the polymerization reaction and vinyl chloride in liquid form is thus prevented from reaching the centres of polymerization.

Tho monomer copolymer i scab In with tho vinyl chloride, whon omployod, may bo added either in tho form of a mixture with the 30 vinyl chloride or separately, in which latter case, either the - 12 - 40204 entire amount or, alternatively only a portion of the total amount of copolymerizable monomer may be present initially in the polymerization vessel, i.e. before commencement of the reaction. In the latter case, the remainder of the copolymerizable 5 monomer may be added either continuously or intermittently during the polymerization reaction.

After polymerization is complete, the polymer product may be processed in a known manner, for example, by coagulation by addition of electrolyte, separation from the remainder of the 10 polymerization reaction product by centrifuging, washing and drying either in a rotary dryer or by spray drying, for example, on a drum dryer.

It is possible to frbricate, from vinyl chloride polymers prepared by the process of the present invention articles which 15 have a much better transparency and a higher impact strength than the corresponding articles fabricated from vinyl chloride polymers prepared by those known processes in which polymerization takes place in the presence of preformed acrylic ester polymer which does not contain units derived from a polyfunctional 20 monomer having at least two non-conjugated ethylenic double bonds and at least one unsubstituted or substituted allylic end group containing one of the double bonds.

This may be demonstrated by reference to the figures of the accompanying drawings. 2 25 Figure 1 shows the notched impact strength in kpcm/cm plotted against the degree of haze in % for 1 mm pressed sheets fabricated from various vinyl chloride polymers each prepared in the presence of a preformed polymer having a mean particle size of between 25 nm and 140 nm. - 13 - 4 0294 Curve 1 relates to vinyl chloride polymers produced in the presence of 3—10% by weight of poly-2-ethyl hexyl acrylate (EHA) and Curve II relates to vinyl chloride polymers produced in the presence of 2-ethyl hexyl acrylate/a-methyl styrene (EHA/MS) 5 copolymers, each of the polymers of Curve I and of Curve II being prepared by a process lying outside the scope of the present invention.

Curve hi relates to vinyl chloride polymers produced in the presence of 2-ethyl hexyl acrylate/allyl methacrylate (EHA/AMA) lO copolymers and Curve IV relates to vinyl chloride polymers produced in tho presence of 2-ethyl hexyl acrylate/u-methyl styrcne/allyl methacrylate (EIIA/MS/AMA) copolymers, each of the polymers of Curve III and Curve IV being prepared by a process lying within the scope of the present invention. 15 It can be seen from Figure 1 that, in comparison with shoots fabricated from polymers each of which has been prepared by a previously known process, sheets fabricated from polymers each of which have been prepared by a process of the present invention in general have a smaller degree of haze for a given 20 notched impact strength (reading values along a horizontal straight line) and a greater notched impact strength for a given degree of haze (reading values along vertical straight line).

Figures 2 and 3 show, respectively, the degree of haze in % 2 25 and the notched impact strength in kpcm/cm as a function of tho porcontage by weight of the preformed polymer which consists of units derived from acrylic ester. Curves II and III corresponding, in respect of the nature of the preformed polymer, to Curves II and III of Figure 1 and Curve IV relating to vinyl chloride - 14 - •I U a 'J J polymers produced in the presence of 2-ethyl hexyl-acrylate/allyl methacrylate/a-methyl styrene (EHA/AMA/MS) copolymers, each of the polymers of Curve IV being prepared by a process lying within the scope of the present invention. 5 It can be seen from Figures 2 and 3 that, in comparison with sjheets fabricated from polymers each of which has been prepared by a previously known process, sheets fabricated from polymers each of which has been prepared by a process of the present invention have, for the same preformed polymer polyacrylic lO ester content, a much smaller degree of haze and a much higher notched impact strength over the entire range of preformed polymer polyacrylic acid ester content. Since the stiffness cf an article fabricated from a vinyl chloride polymer prepared in the presence of a preformed acrylic ester polymer depends 15 primarily on the preformed polymer polyacrylic ester content and decreases as the latter increases, it is possible to prepare, by a process lying within the scope of the present invention, a vinyl chloride polymer having either a higher impact strength for a given stiffness or a high stiffness for a given impact 20 strength as compared to a vinyl chloride polymer prepared by a process lying outside the scope of the present invention.

When a panel of sheet made from a vinyl chloride polymer prepared in the presence of a preformed acrylic ester polymer but by a process lying outside the scope of the present invention 25 is subjected to mechanical stress such as bending or pulling, permanent damage occurs at those places which were subjected to stress and this manifests itself in the form of white spots— tho so-called "white spot effect'". However, sheets made from a polymer prepared by a process lying within the scope of the - 15 - invent ion, mil 1m> hen I to anil Tro, lor example, through IIK)", i:«*|HMl<*(lly willionl .my while !t|M>ljt ix-i-urr lng.

If the preformed polymer contains, instead of units derived from a polyfunctional monomer having at least two non-conjugated 5 cthylcnic double bonds and at least one unsubstituted or substituted allylic end group containing one of the non-conjugated ethylenic double bonds, units derived from a polyfunctional monomer which does not have an end group of this type, but has, for example, units derived from glycol dimethacrylate or 1,3-lO butylene glycol dimethacrylate, the resulting vinyl chloride polymer does not possess the required impact strength and transparency and articles fabricated therefrom do not exhibit the lack of white spot formation.

Since articles having excellent impact strength, transparency 15 and resistance to climatic conditions can be made from polymers prepared by the process of the present invention, these polymers can be utilized in the manufacture of transparent or translucent products, such as panels, pipes, tubes and sections, by extrusion, injection moulding and calendering, and are thus valuable in 20 providing building materials.

Tho process of the present invention is further described with reference to tho following Examples, of which. Examples 1 and 11 illustrate in detail tlio preparation of preformed polymers in tho form of aqueous dispersion (a) for use in processes lying 2f> within tho scope of tho present invention and (b) for comparison, for use in professes lying outside the scope of the present invention. Examples 2 to lO and 12 illustrate, in detail, processes lying (a) within, and, for comparison, (b) outside the scope of the present invention and also illustrate the properties - 16 - 4 0 2 0 1 of articles made by processes (a) and (b).

Tij Kxamptiv* i ;iiul 11, in tin* iMnc ol .\».h .njn.-.MiM .itoprm m l.iiin| <-mii lui ( ii>r KJt) (llayor). 5 In Examples 2 to lO and 12, values for haze, Bradbender torque, notched impact strength and Vicat softening point were determined as follows: Haze: In accordance with ASTM D 1003—61 by means of a Haze-meter 10 (Messrs. Evans Electroselenium Ltd., Halstead, England) using 1mm and 4mm thick sheets obtained by rolling for lO minutes at 180°C on mixing rolls and tljen pressing at 180°C a mixture prepared from 60.5 parts by weight of vinyl chloride homopolymer, 1 part by weight of organic thiostannic stabilizer and 1 part by weight of 15 lubricant, the value (expressed as a percentage) being obtained from the equation: Td Haze = . lOO Tt where Td is the light scattered on passing through the sheet and Tt is the total light transmitted through the sheet. 20 Brabender torque: By kneading a mixture of 57.O parts by weight of vinyl chloride homopolymer, 2.3 parts by weight of barium cadmium stabilizer and O.7 parts by weight of lubricant in either a Type W 30H (Experiment Nos. Ol to 68) or a Type 50 (Experiment Nos. 25 101 to 115) measuring kneader of a Type PL 3 S plastograph (Messrs. Brabender, Duisburg, Germany) at 180°C at 40 rpm. to - 17 - '1 0 2 9 <1 lowest torque reached after gelling of the mixture being taken as an indication of processing properties since the torque is dependent upon molt viscosity.

Notched inuxact str»*i>'itli: 5 In accordancc with DIN 53453 using small standard sticks.

Vicat softening point; In accordancc with DIN 53460.

Example 1.

Polymer dispersions A to U and A' to G* for use in preparing lO vinyl chloride polymers by processes lying, respectively, within and outside tho scope of tho present invention, were prepared as follows:- Desalinated water, lauric acid, caustic soda solution and potassium peroxide disulphate (in quantities as indicated in 15 Table 1) were placed in a 12 litre vessel whose contents could be agitated and, with agitation, were heated to a temperature of 70°C. The vessel was flushed by repeated evacuation and admission of nitrogen under pressure and then pressurised with nitrogen to a pressure of 2 atmosphere gauge. With the vessel at a tempera-2() turo of 70°C, lOOg of monomer were pumped into the vessel over a period of 2 minutes. After a lO minute pause the remaining monomer was pumped into the vessel over a period of 2 hours.

After polymerization at 70°c had been allowed to proceed for 4 hours, the pressure in the vessel was reduced and the vessel 25 was allowed to cool. From each monomer A—U and A"—G' a polymer dispersion was thus prepared, the mean particle diameter of which was determined by soap titration. These values, together with respective compositions of the polymer are given in Table 1. - 18 - TABLE 1 Preformed polymer dispersion Water g LS g NaOH lOn ml KPS g EHA g MS g Polyfunctional monomer Preformed polymer Mean particle diameter nm Composition weight % EHA MS Polyfunctional monomer g a 5650 30 15 5 1000 300 AMA 5 66 76.6 23.0 0.4 B 5640 30 15 5 1000 300 A MA 10 58 76.3 22.9 0.8 C 5625 30 15 5 1000 300 AMA 25 60 75.5 22.6 1.9 0 5610 30 15 5 1000 300 AMA 37.5 56 74.8 22.4 2.8 E 5585 30 15 5 1000 300 AMA 65 58 73.3 22.0 4.8 F 5925 30 15 5 1000 _ AMA 25 55 97.6 2.4 G 5425 30 15 5 1000 500 AMA 25 65 65.6 32.8 1.6 H 5440 30 15 5 1000 500 AMA 10 69 66.2 33.1 0.7 J 5625 30 15 5 1000 300 DAP 25 72 75.5 22.6 1.9 K 5625 30 15 5 1000 300 DAM 25 56 75.5 22.6 1.9 L 5625 30 15 5 1000 300 DAF 25 57 75.5 22.6 1.9 M 5425 30 15 5 1000 500 TAC 25 65 65.6 32.8 1.6 N 5425 30 15 5 1000 500 •CAE 25 74 65.6 32.8 1.6 0 5635 24 12 5 1000 300 AMA 25 108 75.5 22.6 1.9 P 5640 22 11 5 1000 300 AMA 25 124 75.5 22.6 1.9 Q 5625 30 15 5 1300 AMA 30 65 97.7 2.3 R 5940 i 24 11 5 1000 - AMA 25 117 97.6 2.4 S 5940 20 10 : 5 1000 AMA 25 144 97.6 2.4 T 5940 1 29 14.5 • 5 1 1000 - AMA 10 61 99.0 1.0 U 5950 I 11 i 1000 - AMA 10 112 99.0 - 1.0 TABLE 1 (Continued) Preformed polymer dispersion Water g LS g 1 NaOH lOn ml KPS g ! ] EHA : g MS g Polyfunctional monomer Preformed Dolvr.er Mean particle diameter nm Compos itier. v. •eight % EHA MS Polyfunctional monomer g A' 5625 30 15 5 1000 300 EGOM 25 68 75.5 22.6 1.9 B' 5000 25 12.5 5 1000 ; 300 EGDM 65 81 73.3 22.C 4.8 C' 5640 30 15 5 1000 300 BGDM 13 80 76.2 22. e 1.0 D' 5660 22 11 5 1000 300 - 120 76.9 23.1 E' 5950 30 15 5 1000 - - - 60 100.0 - F' 5650 30 15 5 1000 I 300 - _ 60 76.9 23.1 G' 5925 28 14 1 5 1000 - EGDM 25 71 97.6 - 2.4 ■ ) o LS lauric acid KPS potassium peroxide disulphate EHA 2-ethyl hexyl acrylate MS a-methyl styrene AMA allyl methacrylate DAP dic-llyl phthalate DAM diallyl maleate DAF diallyl fumarate TAC triallyl cyanurate TAE tetra-allyl oxyethane EGOM ethylene glycol dimethacrylate BGDM 1,3-butylene glycol dinethacrylate Examples 2—10.

In each of the following Examples 2—10, Experiments were carried out in which vinyl chloride was homopolymerized in the presence of some of the various preformed polymer dispersions given in Example 1, and, in some Examples, in the absence of any preformed polymer, these latter being for comparison. The Experiments were conducted as follows: c K a A, 40204 i Desalinated water, lauric acid, caustic soda solution and potassium peroxide disulphate (in quantities as indicated in Tables 2 to 10) were placed in a 12 litre autoclave whose contents could be agitated and heated to a temperature of 59°C. A preformed 5 polymer in the form of an aqueous dispersion (composition and quantity as indicated in Tables 2 to 10), was introduced into the autoclave during the heating-up period. The autoclave then was evacuated and flushed by repeated admission of vinyl chloride under pressure followed by expansion. With the autoclave at a temperature lO of 59°C, vinyl chloride (in the quantity indicated in Tables 2 to lO) was admitted under pressure to the autoclave. Polymerization was allowed to proceed with agitation until the pressure in the autoclave reached 4 atmosphere gauge. Then the pressure in the autoclave was reduced and the autoclave allowed to cool. The auto-15 clave contained a dispersion having a solids content of 23—25% by weight. The polymer was isolated from the dispersion conventionally by coagulation with electrolytes.

Tables 2 to lO each give values for haze, Brabender torque, notched impact strength and Vicat softening point for each of the 20 polymers prepared.

Example 2.

Data relating to the'Experiments in this Example are given in Table 2. These Experiments included those directed to processes lying within the scope of the present invention in which vinyl chlo-25 ride wa3 polymerized in the presence of a preformed polymer dispersion of ethyl hexyl acrylate/allyl methacrylate/u-methyl styrene. (Experiment Nos. 05—12) and ethyl hexyl acrylate/allyl methacrylate, but no d-methyl styrene (Experiment Nos. 13, 14 and lOl—105). The Experiments also included, for comparison, those directed to - 21 - 4 0 2 9 1 processes lying outside the scope of the present invention in which vinyl chloride was polymerized in the absence of any preformed polymer (Experiment No. 39), in the presence of a preformed homopolymer of ethyl hexyl acrylate, but no polyfunctional monomer 5 (Experiment Nos. AO, 41, 42), in the presence of a preformed polymer of ethyl hexyl acrylate/a-methyl styrene copolymer again with no polyfunctional monomer (Experiment Nos. Ol, 02.03, 04), and in the presence of a preformed polymer of ethyl hexyl acrylate/ ethylene glycol dimethylacrylate, i.e. a polyfunctional monomer lO other than that used in a process lying within the scope of the present invention (Experiment Nos. 67, 68). - 22 - 40204 TABLE 2 Preformed polymer « dispersion Ex Particle NaOH periment diameter Water LS In KPS VC No.

No. nm 9 g g ml g g 01 F' 60 560 5480 lO 60 2 1900 02 F' 60 700 5380 9 50 2 1870 03 F' 60 910 5210 8 45 2 1830 04 F' 60 1190 5000 7 40 2 1780 05 A 66 910 5210 8 45 2 1830 06 B 58 910 5210 8 50 2 1830 07 C 60 910 5210 8 45 2 1830 08 D 56 910 5300 8 50 2 1830 09 E 58 910 5220 8 50 2 1830 lO C 60 560 5490 lO 60 2 1900 11 C 60 910 5390 9 50 2 1870 12 c 60 1190 5000 7 40 2 1780 13 F 55 910 5230 8 45 2 1870 14 F 55 1190 4950 7 40 2 1830 39 - - - 5940 12 60 2 2000 40 E* 60 560 5470 9 50 2 1900 41 E' 60 700 5450 9 50 2 1900 42 E' 60 910 5170 8 45 2 1870 67 G' 71 910 5210 8 45 2 1870 68 G' 71 1190 5000 7 40 2 1780 101 Q 65 430 5590 11 60 2 1920 102 Q 65 560 5480 lO 60 2 1900 103 Q 65 700 5380 9 50 2 1870 104 Q 65 910 5210 8 45 2 1830 105 Q 65 1190 5000 7 40 2 1780 LS = lauric acid KPS = potassium peroxide disulphate VC = vinyl chloride - 23 - 1029 1 TABLE 2 (Continued) (^ontent in * Of Haze in % Brabender Notched Kx- impact |ier imr-nt 1 mm 4 mm . torque strength Vicat No.

EIIA MS AMA EGDM sheet sheet mJcp kpem/cm2 °C Ol 5.7 1.7 _ 5 14 1.5 8.9 76 02 6.2 1.9 - - 6 14 1.6 11.2 75 03 9.2 2.8 - - 9 25 1.5 12.5 76 04 10.3 3.1 - - 12 31 1.4 23.4 75 05 7.9 2.4 O. 04 — 3.5 11 1.6 23.2 76 06 7.2 2.2 0.07 - 3.5 lO 1.6 40.3 76 07 7.5 2.2 O. 19 - 3.0 lO 1.7 44.6 74 08 6.5 2.0 O. 24 - 3.0 14 1.75 28.7 74 09 8.3 2.5 0.54 - 2.5 6 1.80 47.8 74 lO 4.8 1.4 O. 12 - 2.5 7.5 1.6 lO.O 75 1 I 6.1 1.8 0.15 - 3.0 9. O 1.6 33.O 75 12 JO. 3 1.1 O. 26 - 2.5 10.5 1.8 60.9 73 1 » H.5 _ O. 21 8.0 24.O 1.6 38.7 76 14 io.r> - O. 26 - 9.0 32.O 1.6 49. 1 74 39 _ _ _ 3. O 4.0 1.5 3.0 76 40 5.4 - - - 18 n. d. n. d. 10.6 75 41 6.6 - - - 21 n.d. n.d. 14.2 75 42 8. O - - - 40 n. d. n. d. 17.2 75 67 6.4 _ _ ■ 0.16 21 66 2.2 31.7 77 68 9.5 - - O. 24 39 68 2.3 30.8 76 101 4.9 _ O. 11 _ 9 30 2.45 8.5 76 102 5.9 - O. 14 - 9 26 2.25 34.O 76 103 7.1 - 0.16 - 13 38 2.4 51.5 77 104 9.3 - O. 21 - 12 31 2.4 52.O 76 105 12.5 - O. 29 - 19 45 2.5 52.9 76 KI1A = 2-ethyl hexyl acrylate MS = u-mothyl styrene AMA = allyl methacrylate EGDM = ethyleneglycol dimethylacrylate n.d. = not determined Example 3.

Data relating to the Experiments carried out in this Example are given in Table 3. These Experiments were directed to processes (lying within the scope of the present invention) in which vinyl 5 chloride was polymerized in the presence of various preformed polymer dispersions each prepared from the same monomers (ethyl - 24 - <10 2 9-1 lioxyl .wry In I o/i\ 1 I y I nwt harry Inl • v'.i-iwt hy | :m>) ns I hitnn of Kx|'« I.' «*• Kx.»mpl<* I *n I i-.irli r.m t .1111 i ti-i nciMoxi in.it fly ll-*„ >«| ,1 nii'lliyl >i|yi>l V\..

* . ' TAIU.t: I Experiment No.

Preformed polymer dispersion LS g NaOH In ml KPS g VC g NO.

Particle diameter nm g Water g 15 G 65 \ 910 5250 8 45 2 I800 16 G 65 1190 5040 7 40 2 1740 17 G 65 1910 4500 4 25 2 1580 18 H 69 700 5500 lO 60 2 1880 19 II 69 7 OO 5400 9 50 2 1850 20 II 69 910 5240 8 45 2 1800 21 II 69 1190 5030 7 40 2 1740 LS = lauric acid KPS = potassium peroxide disulphate VC = vinyl chloride Ex Content in Haze in % Brabender torque mkp Notched impact strength kpcm/cm2 Vicat °C % O £ 1 mm sheet 4 mm sheet po ri mo nt No.

EHA MS AMA 15 8.9 4.50 0.22 2.0 5.0 1.6 29.2 74 16 10.2 5 1 O. 26 2.0 5.5 1.7 27.0 74 1 / 15.5 7.8 O. 39 2.0 5.0 ' 1.8 39.0 69 IH 5.6 2.H 0.06 3.0 5.5 1.5 7.5 76 19 5.9 3.0 0.06 2.0 6.0 1.6 15.7 76 20 6.8 3.4 0.07 2.0 7.0 1.7 31 5 76 21 10.4 5.2 0.10 2.5 8.0 1.6 35. 3 75 EHA = 2-ethyl hexyl acrylate MS = a-methyl styrene AMA = allyl methacrylate - 25 - <10 2 9 4 Example 4.

Data relating to the Experiments carricd out in this Example • are given in Table 4. These Experiments included those directed to processes lying within the scope of the present invention in which 5 vinyl chloride was polymerized in the presence of preformed polymer in the preparation of which diallyl phthalate (Experiment No. 22), diallyl maleate (Experiment No. 23), diallyl fumarate (Experiment No. 24), triallyl cyapurate (Experiment No. 25), or tetra-allyl oxyethane (Experiment No. 26), was used instead of allyl methacry-10 La to and, for comparison. Experiments directed to processes lying outside the scope of the present invention in which vinyl chloride was polymerized in the presence of preformed polymer in the preparation of which ethylene glycol dimethacrylate (Experiment Nos. 27 and 28) or 1,3-butylene glycol dimethacrylate (Experiment 15 No. 29) was used instead of allyl methacrylate.

TABLE 4 Experiment No.

Preformed polymer dispersion r~ LS g NaOH In ml KPS g VC g No.

Particle diameter nm 9 Water g 22 0 72 910 5210 8 45 2 1830 23 K 56 910 52 lO 8 45 2 1830 24 L 57 910 5210 8 45 2 1830 25 M 65 OlO 5250 8 45 2 1800 26 N 74 910 5240 8 45 2 1800 27 A' 68 910 5210 8 50 2 1800 28 B' 81 910 5210 9 50 2 1830 29 O CO b 700 5380 9 50 • 2 1870 LS •= lauric acid KPS -- potassium peroxide disulphate VC ■= vinyl chloride - 26 - 40294 Table 4 (Continued) Experiment No.

Content in % of Haze in % Brabender Torque mkp Notched impact strength kpcm/cn>2 Vicat oc EI1A MS Polyfunctional monomer 1mm sheet 4mm sheet 22 8.2 2.5 CAP O. 21 3.0 10.0 1.60 27.0 75 23 8.2 2.5 DAM O. 20 3.0 7.5 1.50 23.1 75 24 8.3 2.5 DAF O. 21 3.5 8.0 1.70 43.2 75 25 7.8 3.9 TAC 0.21 2.0 8.5 1.70 22.2 77 26 7.9 4.0 TAE 0.20 2.0 5.0 1.60 23.8 75 27 7.9 2.4 EGDM ' O. 20 8.0 26 1.55 24.6 76 28 7.9 2.4 EGlJfrt 0.51 25.0 56 1.70 49.7 77 29 6.1 1.8 BGDM 0.08 19.0 1.70 25.0 76 EllA = 2-ethyl hexyl acrylate DAF = diallyl fumarate MS = u-methyl styrene TAC = triallyl cyanurate CAP = diallyl phthalate TAE = tetra-allyl oxyethane IWM = diallyl maleate EGDM = ethylene glycol dimethylacry- late BGDM = 1,3-butylene glycol dimethacrylate Example 5.

Experiment No. 103 of Example 2 was repeated but with preformed polymer dispersions of different particle sizes and/or allyl methacrylate content. The data relating to these Experiments are given in Table 5 which also includes, for comparison, that of Experiment No. 103 previously given in Table 2. The processes of these Experiments are within the scope of the present invention. - 27 - 40294 TABLE 5 Preformed polymer dispersion Water g LS g NaOH In g KPS g VC g Temperature °C Experiment No.

No.

Particle diameter nm 9 106 P 55 910 5230 8 45 2 1870 59 103 Q 65 700 5380 9 SO 2 1870 59 107 R 117 910 5210 8.8 45 2 1870 59 108 S 144 910 5210 8 45 2 1870 59 109 T 61 910 5210 8 45 2 1870 59 no U 112 910 | 5210 8.8 45 2 1870 59 LS " lauric acid KPS = potassium peroxide flisulphate VC vinyl chloridc Experiment No.

Cont in % en ts of Haze in % Brabender torque mkp Notched impact strength kpem/cm Vicat °C EHA AMA 1 mm sheet 4 mm sheet 100 8.5 0.21 8 24 1.6 38.7 76 lot 7. 1 O. |(> 1 1 :»» 2.4 5 1.5 77 107 7.8 (). 20 65 «)6 2.5 47.2 77 108 6.6 O. 17 94 97 2.4 30.8 76 109 7.3 0.07 11 38 2.35 34.4 76 llO 1 7-5 0.08 71 99 2.4 45.3 77 EHA = 2-ethyl hexyl acrylato AMA - allyl methacrylate Example 6.

Experiment No. 07 of Example 2, was repeated but with polymerization temperatures of 53°C and 67°C instead of 59°C. The data relating to those Experiments are given in TOble 6 which also includes, for comparison,- that of Experiment No. 7 previously given in Table 2. The processes of these Experiments are within the scope of the present invention. - 28 - 40294 TABLE 6 Preformed polymer dispersion Experiment No.

No.

Particle diameter nm 1 g Water g LS g NaOH In ml KPS g VC g Temperature ^C 30 C 60, 910 52 lO 8 45 2 1830 53 07 C 60 . 910 5210 8 45 2 1830 59 31 C 60. 910 5210 8 45 2 18 30 67 LS = lauric acid KPS = potassium peroxide disulphate VC = vinyl chloride Experiment No.

Contents in % of EHA 30 07 31 8.7 7.5 8.2 MS 2.6 2.2 2.5 AMA O. 22 O. 19 O. 21 Haze in % 1 mm sheet 3.5 3.0 4.0 4 mm sheet 11 lO 12 Brabender torque mkp 1.8 1.7 1.5 Notched impact strength kpcm/cra2 Vicat °C 48.0 44.6 41.8 77 74 75 EHA = 2-ethyl hexyl acrylate MS = u-methyl styrene AMA = allyl methacrylate Example 7.

Experiment Nos. 103 and 109 of Example 5 were repeated but with polymerization temperatures of 52°C and 66°c (instead of 59°C) in the Experiment Nos. 112 and 113, and with the same polymerization temperature (59°C) but with the addition of about 1% by weight of trichloroethyleno (based on the weight of vinyl chloride) in Experiment No. 111. The experimental data and results of these processes, which are also within the scope of the present invention, are given in Table 7. - 29 - / 40294 Table 7 Preferred polymer dispersion Tem Experiment No.

No.

Particle diameter nm g Water g LS g NaOH In ml KPS g VC g Tri g perature °C 103 Q 65 700 5380 9 50 2 1870 - 59 111 Q 65 700 5380 9 50 2 1870 18 59 112 T 61 910 52 lO 8 45 2 1870 - 52 109 T 61 910 5210 8 45 2 1870 - 59 113 T 61 910 52 lO 8 45 2 1870 - 66 IS = lauric acid KPS = potassium peroxide disulphate VC - vinyl chloride Tri = trichloroethylene Experiment No.

Content Haze in % Brabender torque mkp Notched impact strengtt} kpcm/cm in % of 1 nun sheet Vicat oc EIIA AMA •* mm sheet 103 7. 1 O. 16 13 38 2.4 51.5 77 111 8.6 O. 20 14 47 2. O 39.5 74 112 7.1 O. 07 11 33 2.85 42.8 78 109 7.3 0.07 11 38 2.35 34.4 76 113 6.8 0.07 16 46 1.95 19.6 75 EHA = 2-ethyl hexyl acrylate AMA = allyl methacrylate Example 8.

Experiment No. 07 of Example 2, Experiment No. 20 of Example 3. and Experiment No. 24 of Example 4 were repeated but with the addition of 1% by weight of trichloroethylene as controller. The polymerization conditions and the results are given in Tfeble 8. - 30 - <10 2 0 4 TABLE 8 Experiment No.

Preformed polymer dispersion Water g LS g NaOH In ml KPS g VC Tri g Temperature °C No.

Particle diameter nm g 24 L 57 910 5210 8 45 2 1830 - 59 32 L 57 910 5210 8 45 2 1830 20 59 07 c 60 910 52 lO 8 45 2 1830 - 59 34 C 60 910 5210 8 45 2 1830 2C 59 20 H 69 910 5240 8 45 2 1830 - 59 35 H 69 910 5240 8 45 2 1830 20 59 LS = lauric acid KPS = potassium peroxide disulphate VC = vinyl chloride Tri. = Trichloroethylene Ex Contents in % of Haze in % Braden-der torque mkp Notched impact strength kpcm/cm2 Vicat °C periment No.

EHA MS Polyfunctior nal monomer 1 mm sheet 4 mm sheet 24 8.3 2.5 DAF O. 21 3.5 8.0 1.7 43.2 75 32 8.3 2.5 DAF O. 2 I 3.5 8.0 1.35 17.6 75 ()/ 7.5 2.2 AMA O. 19 3. O lo.o 1.7 44.6 74 34 8.1 2.4 AMA 0.20 2.5 7.0 1.4 34.7 74 20 6.8 3.4 AMA 0.07 2.0 7.0 1.7 31.5 76 35 7.6 3.8 AMA 0.08 2.5 1.25 1.25 11.3 75 EHA = 2-ethyl hexyl acrylate DAP = diallyl phthalate MS = a-methyl styrene AMA = diallyl methacrylate DAF = diallyl fumarate Example 9.

Data relating to the Experiments carried out in this Example are given in Table 9 from which a comparison can be drawn of the properties of vinyl chloride polymers obtained by processes both '> within (Experiment Nos. 07, 36 and 38) and outside (Experiment Nos. 03 and 37) the scope of the present invention, and for each respec- - 31 - 10 2 9 4 tivc ease a comparison can also be drawn of the properties of vinyl chloride polymers obtained by processes in which the preformed polymer dispersions employed have coarse (Experiment Nos. 36, 38 and 37 respectively) and fine (Experiment Nos. 07 and 03 respectively) particles. As can be seen from the Table, the vinyl chloride polymers prepared by the processes within the scope of the present invention gave articles having more desirable properties than those prepared by the processes outside the scope of the present invention, irrespective of the particle size of the preformed polymer employed.

TABLE 9 Preformed polymer dispersion Experiment No.

No.

Particle diameter nm g Water g LS g NaOH In ml KPS g VC g Temperature °C 03 F' 60 910 5210 8 45 2 1830 59 07 C 60 910 5210 8 45 2 1830 59 3(> O 108 9lO 5210 8 45 2 1830 59 37 D' 120 910 5210 8 45 2 1830 59 38 P 124 9lO 5210 8 45 2 18 30 59 l»S = lauric acid KPS = potassium peroxide disulphate VC = vinyl chloride 40294 TABLE 9 (Continued) Experiment No.

Content in % Haze in % Brabender torque mkp Notched impact strength kpcn\/om2 of 1 mm shoot 4 mm shoot Vicat °C.

EHA MS AMA ot *>. J -.11 - •».o l.S 12.5 /t> 07 7.5 2.2 O. 19 3.0 lO 1.7 44.6 74 36 7.6 2.3 0.19 5 18 1.7 53.2 74 37 7.8 2.3 - 40 n.d. 1.5 28.4 75 38 7.2 2.2 0.19 n.d. n.d. 1.75 46.6 74 EHA = 2-ethyl hexyl acrylate n.d. = not determined MS = (t-methyl styrene AMA = allyl methacrylate Example lo. 52lO g of desalinated water, 8 g of lauric acid, 45 ml of normal sodium hydroxide solution, 2 g of potassium peroxide disulphate, and 910 g of preformed polymer dispersion B of Example 1 were placed in a stainless steel 12 litre capacity autoclave whose contents could be agitated, with agitation, at 50°C. The autoclave was evacuated and flushed by repeated admission of vinyl chloride under pressure followed by expansion, and then heated to 59°C. At the autoclave temperature of 59°C vinyl chloride was added in a quantity such that tho positive pressure was 8 atmospheres. Additional vinyl chloride was pumped in in batches of lO to 20 g at substantially constant pressure as the vinyl chloride was consumed. After a total of 1830 g of vinyl chloride had been used, the polymerization was allowed to proceed until the pressure had risen to approximately 4 atmospheres, and the unreacted vinyl chloride was expanded and cooled. The polymer was conventionally isolated by precipitation with an electrolyte. - 33 - 40294 'I\il»lo IO !t|ti1 »l.«i !!••• I I • • i ,i viiivl |*i<|yin>'i |«i .'I'.ti "il Willi I In- ■i.-iiur* li-i mill. 11 inn luil iiriimi |>i i-i i i-il | >i 11 ynii'i K' »>l «» 2-tJlhyl li.-xy I aery la to homopolymer (Experiment No. 46).

TABLE 10 Experiment No. 43 46 ' Polymerization pressure atmospheres 8.0 8.0 Content of 2-ethyl hexyl acrylate % 6.4 7.2 Content of u-methyl styrene % 1.9 - Content of allyl mothacrylato % O. 06 - Haze 1mm sheet * 2.5 IO 4mm sheet % 9. O 24 Notched impact strength kpcm/cm^ 10.5 13. 1 Vicat °C 74 74 Example 11.

A preformed polymer as in C of Example 1 was used, except that the 2-ethyl hexyl acrylate thereof was replaced by mixtures of various acrylic esters in accordance with Table 11. - 34 - TABLE 11 Preformed polymer Preformed polymer dispersion Water <3 LS g NaOH lOn ml Monomers (g) Temperature oc Mean particle Composition weight % KPS g acrylic esters MS AMA diameter nm acrylic esters MS AMA WA 5625 30 15 5 900 EHA 100 IPA 300 25 70 62 68 EHA 8 IPA 22 1.9 WB 5625 30 15 5 600 EHA 400 BA 300 25 70 65 45 EHA 30 BA 22 1.9 TO 5625 30 15 5 550 EHA 450 IBA 300 25 70 62 42 EHA 34 IBA 22 1.9 i i WE 5625 30 15 5 850 EHA 150 IBA 300 25 70 66 64 EHA 11 IBA 21 1.9 | WF 1330 7 3.5 2 118 EHA 57 LA 71 5.9 75 48 47 EHA 23 LA 25 2.3 WG 1286 j 6.9 3.4 1.2 172 EHA 10 TDA 1 69 5.7 70 77 67 EHA 4 TDA 27 2.2 WH 1286 ',6.9 1 3.4 2 137 EHA 34 TDA 69 5.7 70 / 45 56 EHA 14 TDA ! 2c 2.3 LS = lauric acid KPS = potassium peroxide disulphate MS = a-methyl styrene AMA = allyl methacrylate EHA = 2-ethyl hexyl acrylate IPA = isopropyl acrylate BA = butyl acrylate IBA <3 isobutyl acrylate LA » lauryl acrylate TDA = tetradecyl acrylate |U © tw tt 40294 Example 12.

'I1w:n< |>i nii'il |»i>lyn)' I li"..ll loll Willi vinyl I'll I 111 lllf. 'tti«* polyim-r ix.ation conditions and the results are given in Tab Ii* 12.

TMil.K 12 Preformed polymer dispersion Ex- Particle NaOH Tem per imen t diameter Water LS In KPS VC perature No.

No. nm g g g ml g g °C 51 WA 62 700 5380 9 50 2 1870 59 52 WA 62 1400 4845 6 35 2 1800 59 53 WA 62 1400 4845 6 35 2 1140 59 54 WB 65 910 5210 8 45 2 1830 59 55 WB 65 1400 4845 6 35 2 1800 59 56 WB 65 1400 4790 5 30 2 1140 59 57 WD 62 1400 4845 6 35 2 1800 59 58 WD 62 1400 4845 6 35 2 1140 59 59 WE 66 700 5380 9 50 2 1870 59 60 WE 66 1400 4845 6 35 2 L800 59 61 WE 66 1400 4845 6 35 2 L140 59 62 WF 48 650 54 IO 8.5 45 2 L470 59 (»3 WF 48 705 5370 8 45 2 1200 59 (>4 WG 77 630 5380 8.5 47.5 2 L680 59 65 WG 77 675 5400 9 jso 2 L360 59 66 WH 45 675 5400 9 45 2 L360 59 LS = lauric acid KPS = potassium peroxide disulphide VC = vinyl chloride - 36 - 40294 Content in % of Haze in % Notched ••• Brabender impact r*x " porimont Acrylic 1 mm 4 mm torque strength Vicat No. ostors MS AMA SllPPt shoot mkp kponvVni? 1 ».l /t.

II.'.

O.:!'» /. / ».n 44. S /4 r«j !*>.*» O. 4l> J.4 9.2 3. 15 37. 1 71 54 6.0 1.8 O. 15 1.8 7.3 2.65 11.9 75 55 11.2 3.4 0.28 2.8 7.7 2.7 50.3 73 56 16.5 5.0 0.41 4.7 15 3.1 44.1 72 57 12.8 3.8 0.32 3.3 9.9 2.9 11.6 73 58 18.6 5.6 0.47 2.1 IO 3.1 14.0 67 59 6.3 1.9 O. 16 2.2 8.7 2.7 13.3 76 60 12.5 3.8 O. 31 2.6 11 2.7 44.5 74 61 17.8 5.3 0.45 5.5 21 3.0 44.0 70 62 6.0 2.4 0. 20 2.1 8.7 2.55 13.6 76 63 7.7 3.1 0.26 2.5 8.2 2.55 41.0 76 64 5.8 2.2 0.18 3.7 15 2.55 14.4 76 65 7.2 2.8 O. 23 3.5 13 2.4 50.2 76 66 5.6 2.3 0.19 2.9 12 2.4 14.0 73 MS = it-methyl styrene AMA = allyl methacrylate - 37 - 4 0 29 4

Claims (9)

1. A process for preparing a vinyl chloride polymer which i*nni)»r i .ujuo-mi:; emulsion |H> I ynu-i i r. i n>| monomer i»• material i'Dii:: i s I i mi i>l vinyl rhloriilo •uul, optionally, at leant oiu» other 5 monomer copolymerizable therewith, in the presence of a water-;soluble initiator, an emulsifier and a dispersed preformed polymer, which preformed polymer consists of at least one copolymer consisting of (i) units derived from at least one acrylic ester, (ii) units derived from at least one polyfunctional monomer having at IO least two non-conjugated cthylenic double bonds and at least one urifjub.sti f.utod or substituted allylic end group containing one of Llit? .said double bonds and, optionally, (iii) units derived from it-methyl styrene.;

2. A process according to claim 1, wherein;15 (a) at least 80% by weight of the said monomeric material is vinyl chloride,;(b) the said preformed polymer consists of at least one copolymer consisting, as a percentage by weight of the total weight of units (i), (ii) and (iii). of from 55 to 94.7% of units;20 derived from at least one acrylic ester containing from 3 to 18;carbon atoms in the ester group, from 10 to O.3% of units derived from tho said at least one polyfunctional monomer and from 35 to 5% by weight of units derived from u-methyl styrene.;(c) the said preformed polymer has a mean particle diameter 25 of from 30 to 150 nm. as determined by soap titration, and;(d) tho said preformed polymer is used in an amount such that from 4 to 20% by weight of tho said vinyl chloride polymer consists of polymeric material containing units derived from the said at least one acrylic ester.;- 38 -;i o 3 a j;

3. A process according to claim 2 wherein the said preformed polymer consists of at least one copolymer consisting, as a percentage by weight of the total weight of units (i), (ii) and (iii), of from 65 to 84.5% of units derived from the said at least one;5 acrylic ester, from 5 to 0.5% of units derived from the said at least one polyfunctional monomer, and from 30 to 15% of units derived from a-methyl styrene.;

4. A process according to claim 2 or claim 3 wherein the said preformed polymer is a copolymer which consists of units;IO derived from two different acrylic esters, units derived from a said polyfunctional monomer and units derived from a-methyl styrene.;

5. A process according to claim 1, wherein;(a) at least 80% by weight of the said monomeric material is vinyl chloride,;15 (b) the said preformed polymer consists of at least one co polymer consisting; as 'a percentage by weight of the total weight of units (i), (ii) and (iii), of from 90 to 99.7% of units derived from at least one acrylic ester containing from 3 to 16 carbon atoms in the ester group and from IO to O.3% of units derived;20 from the said at least one polyfunctional monomer, and;(c) the said preformed polymer has a mean particle diameter of from 30 to ISO nm, as determined by soap titration and;(d) the said preformed polymer is used in an amount such that from 4 to 20% by weight of the said vinyl chloride polymer;25 consists of units derived from the said at least one acrylic ester.;

6. A process according to claim 5 wherein the said preformed polyner consists of at least one copolymer consisting, as a percentage by weight of the total weight of units (i), (ii) and (iii),;of from 95 to 99.5% of units derived from at least one acrylic ester;- 39 -;4 0 21)4;and from 5 to O.5% of units derived from the said at least one polyfunctional monomer.;

7. A process according to claim 5 or claim 6 wherein the .said preformed polymer is a copolymer which consists of units;5 derived from two different acrylic esters and units derived from a said polyfunctional monomer.;

8. A process according to any one of claims 2 to 7 wherein the said preformed polymer has a mean particle diameter of from 40 to 120 nm.;IO

9. A process according to any oi'.e of claims 2 to 8, wherein tho said preformed polymer is used in an amount such that from 5 to IO/, by weight of tho said vinyl chloride polymer consists of |x>| ynii'r ic material con La i n i ikj units derived from the .said at least one acrylic e.ster.;If. IO. A proccss according to any one of claims 3, 4, 7, 8 and;9 whoroin the units derived from the said at least one acrylic ester arc units of which the ester group contains from 4 to 8 carbon atoms.;11. A process according to any one of the preceding claims.;20 wherein at least 9036 by weight of the units derived from the said at least one acrylic ester are units derived from 2 ethyl hexyl acrylate.;12. A process according to any one of the preceding claims wherein the units derived from the said at least one polyfunctional;25 monomer are units derived from a monoallyl or monomethallyl ester of an unsaturated mono-, di- or poly-carboxylic acid, a di-ester of an unsaturated or saturated dicarboxylic acid of cyanuric acid or of phosphoric acid or a di-, tri- or tetra-allyl or methallyl oster of a saturated or unsaturated polycarboxylic acid, or of;- 40 -;40204;cyanuric acid or of phosphoric acid, cach said mono-, di- or polycarboxylic acid being optionally aliphatic or aromatic.;13. A process according to claim 12, wherein the units derived from the said at least one polyfunctional monomer are units;5 derived from allyl acrylate or allyl methacrylate.;14. A process according to claim 12, wherein the units derived from the said at least one polyfunctional monomer are units derived from tri-allyl cyanurate.;15. A process according to any one of the preceding claims,;10 which further includes the preliminary step of forming the said preformed polymer by aqueous emulsion polymerization which emulsion polymerization is carried out in the presence of a water-soluble initiator and as emulsifier, at least one sa(lt of at least one Tatty acid containing from 12 to 18 carbon atoms.;15 16. A process according to claim 15, wherein the emulsifier is present in an amount of from 2 to 12% by weight, based on the weight of tho said at least ono acrylic ester, of the emulsifier.;17. A process according to any one of the preceding claims, wherein tho said onulsion polymerizing of the monomeric material;20 is carried out at a temperature of from 50 to 70°C.;18. A process according to any one of the preceding claims, wherein the said monomeric material consists of, as a percentage by weight thereof, from 80 to 91% of vinyl chloride and from 20 to 3% of at least one a-olefin.;25 19. A process according to any one of claims 1 to 17,;wherein the said monomeric material consists of, as a percentage by weight thereof, from 80 to 91% of vinyl chloridc and from 20 to 3% of at least one? unsaturated e.ster of a carboxylic acid.;20. A process according to any one of claims 1 to 17,;- 41 -;4 0 2 0 '1;wherein the said monomeric material consists of, as a percentage by weight thereof, from 85 to 99% of vinyl chloride and from 15 to 1% of an alkyl vinyl ether.;21. A process according to any one of the preceding claims wherein the said ••mulsion polymerizing of the said monomeric material is carried out in the presence, as emulsifier, of at least one salt of at least one fatty acid containing from 12 to 18 carbon atoms.;22. A process according to claim 21, wherein the emulsifier is present in an amount of from 0.05 to 1% by weight, based on the weight of the said monomeric material, of the emulsifier.;23. A process according to any one of the preceding claims, wherein the said emulsion polymerizing of the said monomeric material is carried out in the presence, as initiator, of at least one water-soluble free radical former.;24. A process according to any one of the preceding claims, wherein the said emulsion polymerizing of the said monomeric material is carried out in the presence of at least one polymerization chain length controller.;25. A process according to claim 24, wherein the said polymerization chain length controller is a mercaptan which is present in an amount of from O.Ol to 0.2% by weight based on the weight of vinyl chloride.;26. A process according to claim 24 wherein the said polymerization chain length controller is a saturated or unsaturated halogenated hydrocarbon which is present in an amount of from 0.1 to 5% by weight based on the weight of vinyl chloride.;27. A process according to any one of the preceding claims, wherein the said omulsion polymerizing of the said monomeric;- 42 -;40294;material is carried out at a pressure of; from 65 to 9996 of the saturation pressure of the said monomeric material at the temporaturo pf polymerization. .;2H. A procossi accordini) to any one of the precediny claims 5 substantially as herein described and exemplified.;29. A vinyl chloride polymer whenever prepared by a process according to any one of the preceding claims.;P. R. KELLY & CO.,;* AGENTS FOR THE APPLICANTS. I - 43 -