JPH01110A - Graft-modified linear polyethylene, its production method, and impact modifiers, adhesives, heat-sealing layers, bonding layers, compatibility enhancers and bonding promoters made of the polyethylene - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to graft-modified α,T polyethylenes having a total density lower than 940 kg/1rL3, processes for their preparation and uses of these polyethylenes.

Prior Art From West German Patent Application No. 1210874991 BAM, polymers containing free carboxyl g', in particular linear high-density polyethylene (d>940y7m3, HDFE)
and branched low density polyethylene (d<940 kg/m
', LDX'Fi) are well known.

These monomers are not suitable as impact modifiers for regular polymers, such as polyesters and polyamides.

Such as polyethylene modified with acrylic acid, ZPIIM♂me corrugated with maleic anhydride, copolymerization of acrylic acid and acrylic esters with ethylene, terpolymers of ethylene, acrylic esters and maleic anhydride. Impact modifiers for polymers known in the art cause discoloration of polyamides and polyesters, are expensive to manufacture with relatively low degrees of conversion, and are still difficult to improve as impact modifiers. It has the disadvantage that there is a lot of room.

Zograft-modified polybetadiene has the disadvantage that its UV I# resistance is insufficient and polymers based on acrylates (eg methyl methacrylate polymers) become brittle even at relatively low temperatures.

OBJECT OF THE INVENTION The object of the present invention is to investigate the advantages and applicability of the monomer known from DE 2108749 A1 and the possibility of its use as an impact modifier for thermoplastic polymers. The object of the present invention is to provide a novel compound which does not have the above-mentioned drawbacks and has good UV resistance and high toughness even at low temperatures.

Means for Solving the Problem The objective is to obtain a 90% polyamide compound grafted with one or more carboxyl group-containing compounds and one or more vinyl aromatic compounds.
It has a reliability as low as 40/m3. 11! This is achieved with polyethylene (I, LDPK).

The present invention provides that the graft modified φ-shaped low density polyethylene has unexpectedly very advantageous properties and is very suitable for use with, for example, polyamides, polycarbonates, polyacetals, vinyl aromatic polymers and polyesters. They are excellent impact modifiers (based on the fact that they have very high UV resistance and a high degree of toughness without fading), and they are also used as adhesives or bonding layers in composite films. Suitable as a bond a, as a heat sealing layer, as a compatibility enhancer for polar and non-polar plastics,
It can be filled with mineral fillers and can also be used in mixtures with other polymers, especially polyolefin homo-Jt& copolymers (e.g. polyprogylene, KPDM rubber, our own polyethylene!4). is also suitable.

They can also be easily tailored to a specific purpose to obtain the characteristics needed at a particular point in time.

The linear low-density polyethylene to be graft-modified according to the invention can be prepared from carboxyl it-containing conventional polyethylene grafting substances such as acrylic acid, methacrylic acid,
Maleic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, endo-cis-dicyclo(2,2,1)A,
Boudot-5-ene-2,3-dicarboxylic acid and bicyclo(
2,2,1) Hept-2-ene-5,6-dicarboxylic acids, it is advantageous to graft with derivatives of these acids, such as their acid halides, amides, imides, anhydrides, esters and salts. Examples of these derivatives are maleyl chloride, maleimide, acrylamide, methacrylamide, cricidyl methacrylate, maleic anhydride, itaconic anhydride, reactor water citraconic acid, bicyclo(2,2,
1) Hept-2-ene-5゜6-dicarboxylic acid anhydride, monomethyl maleate, dimethyl maleate, chrycidyl maleate, dimethyl fumarate, diethyl itaconate, dimethyl citraconate, dimethylbisic I'm (2,2 , 1) Hepto-2-ethylene-5゜6-dicarboxylate, methyl acrylate, methyl methacrylate, glycidyl acrylate, sodium acrylate, sodium methacrylate, potassium methacrylate,! Disodium oleate, dipotassium oleate, sodium maleate, disodium fumarate, dilithium itaconate, diammonium citraconate, disodium bicyclo(2,2,1)hept-2-ene-5,6 -dicarpoxylate, 4-methylcyclohex-4-ene-
1,2-dicarboxylic acid anhydride, 1.2.3.4.
5゜8.9.10-octahydronaphthalene-2゜3-
Dicarboxylic anhydride, bicyclo(2゜2.2)oct-7-ene-2,3,5,6-tetracarboxylic acid-
2,3,5,6-dianhydride, bicyclo(2,2,
1) Hept-5-ene-2,3-dicarboxylic acid anhydride, methylbicyclo(2,2,1)hept-5-ene-2,3-dicarboxylic acid, 7-oxabicyclo(2,2
, 1) hept-5-ene-2,6-dicarboxylic acid anhydride. It is also possible to use mixtures of these substances.

For example, the vinyl aromatic compound used to graft forest low density polyethylene is 3-substituted styrene, such as R-styrene, where R is an alkyl group having 1 to 10 return atoms. Mixtures of vinyl aromatic monomers can also be used.

The molar ratio of vinyl aromatic monomer to carboxyl group-containing compound is, for example, from 5:1 to 1:5, particularly from 2:1 to 1:2.

For example, m-shaped low density polyethylene grafted with a mixture of styrene and maleic anhydride in a molar ratio of 5:1 to 1:5, in particular 2:1 to 1:2, is a particularly advantageous impact-resistant thermoplastic polymer. It was found to be a sex improver.

Very low density (density<915kg/7FL') (VLD
PE), especially density <9101 #/m', especially ≦900k
Excellent results are achieved when using a graded polyethylene of g/7FL3. Generally, the density is 870 kg/m
3 or lower (none), especially lower than 880 kg/m3 (none).

For example, linear polyethylene suitable for grafting is
It is a covalent polymer with one or more α-olefins having 3 to 8, especially 5 to 12 ethylenetocarbon lumi atoms. It is also possible to use ethylene terpolymers (eg propylene or butylene and alpha-olefins having 5 to 12 hydrogen atoms). Furthermore, large or small amounts of dienes (e.g. 1,
Polyunsaturated compounds such as 9-decadiene) may also be present. The highest melting point as measured by differential scanning calorimetry is 100-150°C, and also by DSQ method]
The determined crystallinity at 23° C. is at least 10%, in particular at least 20%.

For example, these Ivil-like polyethylenes or mixtures are
177'lopyrene, ethylene/furo-trene copolymer,
It is also advantageous to graft with other polyolefins such as ethylene/propylene terpolymers, other polyethylenes, polybutadiene or mixtures thereof, etc. However, at least 5% by weight of the mixture, in particular 1% by weight
In particular, 301% by weight consists of m-shaped low density polyethylene.

Melted low density polyethylene according to the invention and very low g &
I degree polyethylene (V'LDP) Ic) can be used as a catalyst for transition compounds, especially Ziegler e-Natsuta (Ziegler e Natsuta).
ler-Natta) using a catalyst (for example, GB 1235062). In particular, in addition to titanium compounds, vanadium compounds are also present, and also halogen compounds, especially organohalogen compounds. It is advantageous to use catalysts containing titanium, vanadium, organoaluminum, one or more organohalogens and optionally more than 1 or more diorganomagnesium compounds. The polymer may contain conventional additives such as stabilizers, leakage agents, etc.

For the purpose according to the invention, it has been found that grafting 0.2 to 20 m1% of a carboxyl group-containing compound to polyethylene yields an effective U'''C, in particular 0.5 to 15 wt.%, in particular 1 to 10 m1. Graft with Jugetsu%.

A method of grafting onto styrene/maleic anhydride onto polymers with active or labile hydrogen atoms, such as polyethylene, is described in DE-A-2108749. If polyethylene is used, the process converts the mixture of styrene and oleic anhydride with the polyethylene at temperatures above about 120°C.

This method can be applied to produce polyethylene according to the invention, in which the use of solvents and radical catalysts to promote the reaction is advantageously avoided. However, it has been found that the use of solvents, especially polar solvents such as ketones, eg acetone, and/or the use of radical initiators such as peroxides and azo compounds increases the grafting rate, degree of grafting and conversion.

The high shearing action which brings about the intimate contact of the materials to be grafted is also relevant.

Therefore, the present invention provides polyethylene with one or more carboxyl group-containing compounds and one or more vinyl aromatic compounds under the action of shearing forces at temperatures above 110°C.
It also relates to a process for producing graft-modified low density polyethylene by conversion in the presence of a radical catalyst and optionally an antioxidant.

According to an advantageous embodiment of the invention, the grafting reaction is carried out for intimate mixing of the reactants when using a styrene/maleic anhydride molar ratio of 5:1 to 1:5, in particular 2:1 to 1:2. It is advantageous to graft a suitable low density polyethylene by carrying out the grafting in an apparatus at a temperature range of 110-200° C. with a strong fJIJ cleavage effect; in this method, a solvent such as acetone is added to the entire graft material. to 1 ratio of 5:1 to 1:20. In particular, 2=1 to 1:10 and organic peroxides, such as dialkyl peroxides, diaryl peroxides, diacyl peroxides, organic peroxides,
Organic fast-brewing esters, alkyl hydroperoxides, aralkyl peroxides, or azo compounds are used in particular in an amount of o, o i to 0.5 m-%, based on the polyethylene. The residence time in the reactor is then advantageously between 1 and 15 minutes. Before the mixture leaves the reactor,
The solvent and the monomer can be removed in a customary manner, for example with a degassing agent, and the graft-modified polyethylene can then be granulated or otherwise modified. To avoid any cross-linking, antioxidants, such as phenolic or thiophenolic antioxidants, such as TD Ike/7x (X
rganox) 1076R, Irganox 101
0R or di-t-butyl-p-Fure! - Advantageously, it is added thereto.

These antioxidants do not affect the graft,
Prevents undesired crosslinking.

Reactors capable of grafting carboxyl group-containing compounds and vinyl aromatics onto polyethylene while exerting strong shearing effects include, for example, Brabender 21 and -screw or twin-screw extruders, which are suitable for fph distillation. It may be connected to one or more stationary mixers for different opening times.

The molten polyethylene is fed into such a surface device and melted therein, with a solution of the graft compound optionally containing 'Fs-' in the radical initiator and/or antioxidant being applied to the molten polyethylene. and intimately mix with the f-fluid under strong shear to carry out the grafting reaction. It is advantageous to graft the vinyl aromatic compound onto the polyethylene before or together with the carboxyl group-containing compound.

The graft modified polyethylene according to the present invention is A3TM D
Melt index 0 as measured by -1238-E
．． 01 to 50 #/10 min, and 10 to 90 as an impact modifier for e.g. polycarbonates, polyacetals, vinyl aromatic polymers, polyamides and polyesters.
, especially in an amount of 20 to 80% by weight.

They can be mixed with the respective polymer in an extruder in a known manner. The particle size of the graft polymer is advantageously small, for example <0.5 μm, especially <0.1 μm, and >0.001 μm, especially 0.005 μm.

Polycarbonates can be produced by ffEIs with phosphorus, dihydroxy- or polyhydroxy compounds or carboxylic acid diesters as known in the art. Particularly suitable dihydroxy compounds are dihydroxydiarylalkane, for example those having an alkyl group or a chlorine or bromine atom in the ortho position to the hydroxyl group.

The following compounds are excellent photodihydroxydiarylalkane: 4,4'-dihydroxy-2-diphenylpropane (bisphenol A), tetramethylbisphenolum, tetrachlorobisphenol A1 tetrapromobisphenolum, bis(4,- hydroxyphenol)-p-diisopropylbenzene. In addition to polycarbonates which can be produced solely from dihydroxydiarylalkane, branched polycarbonates can be used. In producing this type of polycarbonate, the dihydroxy compound can be replaced by a polyhydroxy compound.

Polyacetal is a crystalline thermoplastic.

Examples of polyacetals are homopolymers of formaldehyde and copolymers of trioxane (ie, trimers of formaldehyde) with ethylene oxide and small amounts of cyclic ethers such as 1-32 dioxane. These polyacetals can be used separately or in mixtures.

The vinyl aromatic polymer is styrene, substituted styrene, Example 1-
! : Homopolymers and copolymers of vinyl aromatic monomers such as α-methylstyrene, while butadiene (8B
R), acrylonitrile (BAN), maleic anhydride (8MA), butadiene/acrylonitrile (
AB8) etc. can also be used as comonomers.

The polyamides may be aliphatic, cycloaliphatic and aromatic diamines such as hexamethylene diamine, decamethylene diamine, dodecamethylene diamine, 2.2.4- or 2.4.
4-) Limethyl-hexamethylene diamine, 1,3- or 1,4-bis(aminomethyl)-cyclohexane, bis(p-7Znocyclohexyl)methane and m- or p-xylene diamine with aliphatic, fatty % and lactams by polycondensation of cyclic and aromatic dicarboxylic acids, such as adigic acid, speric acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid and isophthalic acid,
For example, copolyamides of these materials obtained by condensation of e-caprolactam and ω-lacrolactam are also useful. These polyamides can be used separately or in mixtures.

Typical examples of the polyamide are nylon 6 and nylon 4.
．． 6, nylon 6.6, nylon 610, nylon 9,
They are nylon 11, nylon 12, nylon 6/66, nylon 66/610 and nylon 6/11.

Polyesters include aliphatic glycols such as ethylene glycol, phloylene glycol, 1,4-butanediol, neopentyl glycol and hexamethylene glycol, cycloaliphatic glycols such as cyclohexane dimetatool, and aromatic dihydroxy compounds such as bisphenol. a dihydroxy compound constituent unit comprising at least 11t pace of a compound selected from the group consisting of;
Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid, aliphatic dicarboxylic acids such as succinic acid, conolilic acid, adipic acid, sebacic acid and kundekadicarboxylic acid, and M? A crystalline thermoplastic resin formed from at least one dicarboxylic acid selected from the group consisting of WX dicarboxylic acids, such as tetrahydroterephthalic acid. Polyesters can be modified with small amounts of trihydroxy- or polyhydroxy compounds and polycarboxylic acids, such as triols and tricarboxylic acids, if the modified resin is thermoplastic. This polyester can be used alone or in wet form.

Illustrative examples of said polyesters are polyethylene terephthalate, polypropylene tere7thalate, polyethylene terephthalate and polyethylene isophthalate/
It is a terephthalate copolymer.

The basic object of the graft-modified linear low-density polyethylene according to the invention is its use as an impact modifier for the polymer. However, it can also be processed by conventional methods, such as melt extrusion, to form shaped articles such as films, tubes, wire fibers, etc., advantageously using the same extruder in which the grafting was carried out. be. The resulting film may be a single layer or multilayer film.

Furthermore, the graft-modified fibrous low-density polyethylene according to the invention can be used as an adhesive, bonding layer or bonding layer between layers of different materials, such as other polymers (e.g. polyolefins), metals, paper, etc. , i.e. for the production of multi-composite materials, such as the bonding of polymers and polymers, polymers and metals, as well as glass, woven or non-woven fabrics or mats, paper, etc.

The polyethylene according to the invention can be used as a heat-sealing layer for one material, for example other polymers, in particular polyolefins, such as polyethylene or polypropylene. If graft-modified linear low-density polyethylene is used as the film layer, the surface of the polymer film to which the graft-modified polyethylene according to the invention is applied is often subjected to electrical discharge or flame treatment to improve adhesion. There is no need to apply an adhesive film or adhesive film.

The polyethylene according to the invention can also be processed into foamed products using conventional blowing agents. Furthermore, the graft-modified linear polyethylene according to the present invention can be processed into fibers by, for example, a melt spinning method or a film threading method, and the fibers can be processed into woven or unwoven fabrics by drawing strings. can be formed. Woven and non-woven fabrics can be printed with conventional paper or textile proofing and printing compounds.

In particular, the graft-modified linear low-density polyethylene according to the invention is also suitable as an agent for enhancing the compatibility of incompatible or poorly compatible materials. For example, with respect to polyolefins such as polyethylene, polypropylene, etc., if this is the polyethylene according to the invention
Bunch amount %, especially at least 10! It can be mixed with glass if it contains fi%. Furthermore, the polyethylene according to the invention has a content of at least 5Xf for all monomer composites.
It is also possible to mix polar and non-polar polymers when adding t%, in particular at least 10% by weight.

The grafted molten low density polyethylene according to the invention can be used as a component of a mixture or blend.
~95%, especially 10~90%, especially 15~
It can also be used in amounts of 85% by weight. Other components of such mixtures are plastics, such as polyoleins (homomers and copolymers of ethylene and propylene), optionally vinyl aromatics, monomers with carboxyl rings t-i, etc. Homopolymers and copolymers as well as other graft polymers may be used. Other ingredients are
It may also be made of materials other than polymers, such as glass, Merck, carbon black, metal, wood, paper, etc.

lol gfq example Next, a detailed explanation will be given using an embodiment of the present invention.

Example 1 To implement this example, we will use the crystal pressure radical initiation method
L&min a, [LDPE (a -918 kg/m',
Melt index MX” 8 dg/min
) t-use.

A 2:2:1 mixture of styrene, maleic anhydride, and acetone was added to the polyethylene in a chemistries connected to a stationary Kennias mixer on the outlet side.
Graft in an axial screenie extruder.

The ethylene was maintained at a temperature of 150° C. and the screening speed was 150 rl) I! 1 into an extruder. Add styrene (8), maleic anhydride (MA) and acetone (2:2 of Aron) to the position where the polyethylene melts.
:1-Feed the mixture to the extruder. polyethylene and 8
/MA/AO- The styrene/maleic anhydride is grafted onto the polyethylene as the mixture is passed through an extruder and through a stationary mixer maintained at a temperature of 150°C. The residence time was approximately 11 minutes.

1 of passed polyethylene (Pll), fed 8 7
MA/MUC], Use of peroxide initiators and stabilizers premixed with granular polyethylene (PI) fed in an extrusion manner M, UM Feeding 31 (1'l++ if!
% (therefore the corresponding amount of styrene was also used, the 3 for bound styrene is not stated), the conversion rate and the melt index of the resulting grafted product are expressed as 1st! ! ! Example 2 described in Example 1 is repeated, but in Experiments 1 and 2 VLD#E((L−
902kg/m3, M knee 2-2 dg/min)
In experiments 6 to 20, vLDr1! i(a -900k
y/m3, M knee 2.24g/min) k is used. The peroxide used was Trichonox cR.

The details and results of this experiment are listed in Table 2.

tai 2 Table Example 6 The polyethylene used was Lp:px (97 to a-918).
m3, M knee 8ag/win). The grafting reaction is carried out in a two-wheel screw extruder (WPZ8K 42 D) at the temperatures listed in Table 3 below. Experiments 1-7
The FE is mixed with tMA in an amount of 5% relative to PK before being fed to the extruder, and the styrene is injected into the extruder.

In runs 8-14, styrene, leicic anhydride, and acetone (2:2:1 weight ratio) were fed to the t-extruder. Tridenox OR was used as peroxide catalyst.

Table 3 below lists the experimental conditions and the melt index of PI.

Example 4 In this example, in experiments 1 to 6, LDPK (d -918kg
/m35M knee 84g /'Win) in experiments 7-9 vIIDpI! l(a -900XF/m', MI-
The extruder used was as described in Example 3, and the peroxide catalyst used was a Tri-Knox OR.

A description of Experiments 1-9 and the melt index of the resulting grafted polyethylene are shown in Table 4.

Example 5 In this example, VLDPE (a = 900 kg/m'
, MI=2.2 d, ji//min). The twin-screw extruder used was the one mentioned in Example 3, and the method described also applies. The temperature of the extruder is 190℃
and the peroxide catalyst is Tribonox CR. The results are shown in Table 5.

Example 6 vLDPE (d = 902 kg/m”, MI =
2.24 g/min) in the same extruder as described in 5116. In experiments 1 to 6, a 1:1 mixture of MA/acetone was used as the grafting material, with a real number of 7 to 12
In experiments 16-18, styrene/MA/acetone 2:2 - mixed conversion of styrene/acetone.
:1-Use a mixture.

In runs 19-21, the MA-grafted products of runs 1-3 were grafted with a 1:1 mixture of styrene/acetone, and in runs 22-24, the styrene-grafted products of runs 7-9 were grafted with MA/1-mixtures of styrene/acetone. Graft with a 1:1 mixture of acetone.

The peroxides used include Trigonox-C” 0.052 to 1 as shown in Table 4.
1% or Luperox 130
"0.05] LM% and Irgano
x) 1076 [F] o, o sm violet% was added as a stabilizer at °C.

Maintain temperature at 190'C and screw speed at 25 O.
They were r, p, m. The throughput was 679/min. The results are shown in Table 6.

Examples 7 to 17 illustrate the use of grafted linear polyethylene according to the invention to modify the impact strength of thermoplastic polymers.

The following properties are measured on polyamides with varying impact strength: Impact strength (measured by l5O180)E
-Module (measured according to ASTM-D-790)
Dimensional stability (measured according to ISOR527-1) Maximum bending strength (measured according to SOR27-1) Breaking strength (measured according to ASTM-D-790).

Example 7 This example shows polyamide 6, polyamide 6.6, and polyamide 4.64-1 grafted LDPE with S/MA according to example 1 for comparison (d = 918 to 97 m”).
, MI=8 dp/min) as a force, ? VLDPE grafted with S/MA by I12
(a = 9 Ll 2 kg/m", MI = 2
．． 0 polyamide/graph showing a mixture with 2d, V/m1n) PE mixing ratio is 80/20.

Mixing is carried out in a twin-screw extruder at a temperature of 240°C if polyamide 6 is used; at a temperature of 275°C if polyamide 6.6 is used and at 310°C if polyamide 4.6 is used. .

The properties of the modified polyamide can be derived from the following seventh layer.

Example 8 In this example, the conditions were the same as described in Example 7, except for the change in the polyamide 6/grafted PE mix ratio.

The details can be derived from the eighth garment.

Example 9 In this example, the S/MA according to Example 2 and the grafted VL
DPE (a=902 to 9/m3, MI=2.2d, j
9/m1n) and VLDPE (a = 900kg/
m', MI = 2, 2 dg/min) is mixed with nylon 6 (PA 6 ) in a manner similar to that described in Example 7.

Conditions and product characteristics are shown in Section 9.

Example 10 In this example, VL is grafted with S/MA according to Example 2.
DPE (d = 900 kg7m3, MI = 2
．． 2 dg/mln) is mixed with nylon 6.6 in a manner similar to that described in Example 7.

The results are shown in Table 10.

Example 11 In this example, VLDPE grafted with S/MA with fl]4 (d = 900 kg/m', MI =
2.2 dg/mln) is mixed with nylon 6 in a manner similar to that described in Example 7.

The experimental conditions as well as the properties of the product are shown in Figure 11 below.

Example 12 In this example, the Grateau-modified VLDPE of Example 6 (a =
902 kg/m3, MI = 2.2 d! ! / m
in ) with nylon 6 and PA in a similar manner as described in Example 7.
Mix at a ratio of 80/PE20. The experiment number corresponds to that of Example 6.

The results are shown in Figure 12.

The example in Example 1 is similar to that in Example 7 with nylon 6 and LDPE for comparison (a=918 kl?/m", M!=8
dg/min) and LVDPE as an example.
(d = 900 kg/m3, MI = 2.2ay
/ min ) and LDPE grafted with S/MA according to Examples 3 and 4, respectively.

The experimental conditions and properties of the modified nylon are shown in the following 16th article.

Example 14 This example uses nylon 6 and LDPE for comparison (d =
9181<g/m3, MI=8 dg/min
), and as an example VLDPE (d =
900 klil/m3, Ml = 2.2 dg/
min ) and LDPE grafted with S/MA according to Example 3 and Example 4, respectively.

The experimental conditions and properties of the modified nylon are shown in Figure 14.

Example 15 This example uses nylon 4.6 as in 9117 and LDPE for comparison (a = 918 kg/m"
, MI = 8 d, 9/min) and an example VLDPE (a = 902 kp/m'', ``I = 2.
2 dJ//min) and LDPE grafted with S/MA according to Examples 6 and 4, respectively.

The experimental conditions and properties of the modified nylon are shown in Figure 15.

In the example in Example 1, photographs (8500x) of the mixture of experiment number 2 (comparison) of the mixture according to example 8 and experiment number 10 (invention)
A photograph (6800x) is shown. For the purpose of this photo,
8/MA-LDPE-PA-mixture and S/MA-
The VLDPE-PA mixture was etched with oxygen plasma. These photos show the grafted LDP
VLDP grafted with E particles (up to 0.6μ)
It shows that it is larger than the E particle (up to 0.07 μm).

ψ1j17 In this example, the commercially available impact denaturation deposit 1 for comparison example 4
VLDPE grafted with S/MA according to (d =
902 klil/m3, MI = 2.2 d, s
7/m1n) and polyethylene terephthalate (ArnizeAl 04-9L]0) as an example. See Garment 16.

[Brief explanation of drawings]

FIG. 1 is a photograph showing the particle structure of the mixture of Experiment No. 2 (comparison) in Example 8 of the present invention, and FIG. 2 is a photograph showing the particle structure of the mixture of Experiment No. 10 (invention). Agent Patent Attorney Toshio Yanof::','7'')1
, ′・1 , ′−”−′−1

Claims (1)

[Scope of Claims] Graft-modified linear polyethylene having a density lower than 1,940 kg/m^3, in which polyethylene is grafted with one or more carboxyl group-containing compounds and one or more vinyl aromatic compounds. A graft-modified polyethylene characterized by: 2. The polyethylene according to claim 1, wherein the carboxyl group-containing compound is maleic anhydride. 3. The polyethylene according to claim 1 or 2, wherein the vinyl aromatic compound is styrene. 4. The polyethylene according to any one of claims 1 to 3, wherein the molar ratio of the vinyl aromatic compound to the carboxyl group-containing compound is 5:1 to 1:5. 5. The polyethylene according to any one of claims 1 to 4, wherein the amount of the carboxyl group-containing compound is 0.2 to 20% by weight based on the polyethylene. 6. Polyethylene according to any one of claims 1 to 5, wherein the linear polyethylene has a density <915 kg/m^3. 7. The polyethylene according to claim 6, wherein the density of the linear polyethylene is <910 kg/m^3. 8. Any one of claims 1 to 7 for the entire mixture
Graft-modified linear polyethylene 5 to 95 described in
% by weight and from 5 to 95% by weight of mineral fillers and/or other thermoplastic polymers. 9. A method for producing graft-modified polyethylene having a density lower than 940 kg/m^3, in which polyethylene is sheared with one or more carboxyl group-containing compounds and one or more vinyl aromatic compounds at a temperature higher than 110°C. A process for the preparation of graft-modified polyethylene, characterized in that it is converted under the action of force in the presence of a solvent and/or a radical initiator and optionally an antioxidant. 10. The method of claim 9, wherein the vinyl aromatic compound is grafted onto the polyethylene before or together with the carboxyl group-containing compound. 11. The method according to claim 10, wherein the vinyl aromatic compound is grafted onto the polyethylene together with the carboxyl group-containing compound. 12. Impact modifier using a polyethylene or a mixture according to any one of claims 1 to 8 as an impact modifier or a component of such a modifier. 13. Adhesives using a polyethylene or a mixture according to any one of claims 1 to 8 as an adhesive or adhesive layer or as a component of such an adhesive or adhesive layer. 14. A heat-sealing layer using a polyethylene or a mixture according to any one of claims 1 to 8 as a heat-sealing layer or a component of such a layer. 15. Tie layer using a polyethylene or a mixture according to any one of claims 1 to 8 as a tie layer in a multilayer film or as a component of such a tie layer. 16. A compatibility enhancer using a polyethylene or a mixture according to any one of claims 1 to 8 as a compatibility enhancer or a component of such an agent. 17. A bonding promoter using a polyethylene or a mixture according to any one of claims 1 to 8 as a bonding promoter for polymers and fillers or as a component of such a promoter.