CS261165B1 - A mixture of plasticized polyvinyl chloride - Google Patents

Abstract

A mixture of plasticized polyvinyl chloride containing, in addition to conventional components, such as plasticizers, stabilizers, lubricants, pigments, fillers and surfactants, 1 to 50% by weight, preferably 3 to 30% by weight, of heterogeneous waste, based on polyvinyl chloride and/or vinyl chloride copolymers, with an admixture of fibrous material and further 1 to 15% by weight, preferably 3 to 10% by weight, of copolymers or mixtures of copolymers of vinyl chloride and/or 0.1 to 5% by weight, preferably 0.5 to 2% by weight, of polyolefin oil, e.g. polypropylene oil with a molecular weight of 250 to 600, or the same amount of a mixture of polyolefin oils. The main benefit lies in the fact that the presence of modifying additives - copolymers or mixtures of copolymers of vinyl chloride and/or polyolefin oil, respectively. mixtures of such oils positively affect the flow behavior of polyvinyl chloride mixtures containing heterogeneous waste and thus enable their problem-free processing by rolling.

Description

The invention relates to a mixture of plasticized polyvinyl chloride containing a high proportion of heterogeneous waste, which is intended primarily for flat shapes produced by rolling.

In the field of rubber and plastics technologies, heterogeneous waste is understood as waste that, in addition to the basic polymer component, contains fibrous filler, fibrous reinforcement, residues of individual fibrous layers of laminated products, etc. Heterogeneous waste is generated primarily during the production, or possibly during the processing, of materials such as synthetic leather, flooring, conveyor belts, etc.

There are both economic and ecological reasons for using these wastes in various types of products. From an economic point of view, this is primarily an effective use of mostly still valuable secondary raw materials, while the costs that otherwise have to be spent on their disposal - in the form of landfill or incineration - cannot be neglected. It is obvious that the latter methods of disposal of heterogeneous waste are also completely unsuitable from an ecological point of view - negative impact on the environment, exhalations, etc.

As regards reprocessing, heterogeneous wastes are applied mainly in mixtures for products manufactured by injection molding, extrusion or pressing, where it is either possible to guarantee the achievement of the required degree of their dispersion in the mixture or, conversely, this requirement is not very important. When processing these mixtures by rolling, especially by the process of their gradual plasticization on two rolls and subsequent rolling of the film on a multi-roller, the requirement of a high degree of homogeneity of the mixtures is paramount. In this case, the imperfect dispersion of heterogeneous wastes in mixtures leads to processing difficulties - the presence of a textile component negatively affects the flow properties of the rolled mixture (especially during its plasticization on two rolls), which is manifested by the difficult formation of the mixture belting on the rolls and its instability, i.e. the belted mixture falling off the rolls. The produced film has a poorer quality compared to conventional films, mainly due to the contained unprocessed waste clusters, or due to holes, etc. However, until now there has been no known solution that would reliably eliminate these problems.

The plasticized polyvinyl chloride mixture according to the invention contributes to the elimination of all the above-mentioned shortcomings. The essence of the invention lies in the fact that this mixture, in addition to conventional components, such as plasticizers, stabilizers, lubricants, pigments, fillers and surfactants, contains 1 to 50% by weight, preferably 3 to 30% by weight, of heterogeneous waste, mainly based on polyvinyl chloride and/or vinyl chloride copolymers, with an admixture of fibrous material and also 1 to 15% by weight, preferably 3 to 10% by weight, of copolymers or mixtures of vinyl chloride copolymers and/or 0.1 to 5% by weight, preferably 0.5 to 2% by weight, of polyolefin oil, e.g. polypropylene oil with a molecular weight of 250 to 600, or the same amount of a mixture of polyolefin oils.

The main benefit of the mixture according to the invention lies in the fact that the presence of modifying additives - copolymers or mixtures of copolymers of vinyl chloride or polyolefin oil, mixtures of polyolefin oils, or a combination of both of these types of modifying additives positively influences the flow behavior of polyvinyl chloride mixtures containing heterogeneous waste and thus enables their problem-free processing by rolling, especially during plasticization on plasticizing twin rolls. The produced film, with its values of physical and mechanical properties, practically equals films produced from mixtures that do not contain heterogeneous waste as an additive.

The following practical examples serve to further clarify the essence of the invention, where rheological measurements on a Brabender plastograph were used to objectify the evaluation of the flow behavior of the mixtures. In this case, the value of the torque Μ^θ (Nm) recorded after 30 minutes of measurement at a given temperature can be considered as a measure of the viscosity of the melt of the mixture. The dependence of ln Μ^θ on the inverse value of the absolute temperature then provides the so-called flow line, the position of which is a measure of the flow behavior of the evaluated mixture. Lower ln values mean lower viscosity of the melt of the mixture, i.e. more favorable flow behavior from the point of view of the rolling process. For a standard mixture without the addition of heterogeneous waste, the ln values lie in the range of 1.57 to 0.97 for the temperature range of 150 to 180 °C. With the help of the above-specified modifying additives, the flow behavior of mixtures with heterogeneous waste can be adjusted so that their flow lines are very close in position to the flow line of the standard mixture, or lie in the region of even lower ln M _k30 values.

The examples include mixture recipes documenting the essence of the invention. The effectiveness of individual solutions is always expressed by the position of the flow line - the values of ln at temperatures

150, 160, 170 and 180 °C.

Example 1.

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 22.5 polyvinyl chloride suspension K = 60 7.5 dioctyl phthalate 5.4 dibutyl phthalate 0.6 micronized limestone, very finely ground, type 10, particle size less than 31.8

0.063 mm heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) 0.5 heterogeneous waste with 25.6% textile component, particle size up to 4 mm 30.0

100.0 was prepared by mixing the individual components in a fluid mixer. It is clear that this is a mixture with heterogeneous waste (the textile component is 7.7% of the total weight of the mixture), but without the addition of modifying additives. This recipe therefore represents the state of the art before the introduction of the solution according to the invention.

By measuring the flow behavior on a Brabender plastograph, the following values ^{of In M} k30 were determined ^: temperature (°C) 150 160- 170 180 ln M _k30 2.12 1.95 1.78 1.64

In accordance with these values, it was further found that plasticization of the mixed mixture on a double roller cannot be carried out. The mixture is very difficult to combine, the formation of the girdle is very lengthy and the girdle does not hold on to the front (working) roller.

Example 2

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 22.5 polyvinyl chloride suspension K = 60 7.5 dioctyl phthalate 4.0 dibutyl phthalate 0.5 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 31.8 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) 0.5 heterogeneous waste with 25.60% textile components, particle size up to 4 mm 30.0 polypropylene oil Κ 1,000 (with mol. wt. 430) 1.5

100.0 was prepared similarly to example 1 by mixing all the components in a fluid mixer. The weight fraction of the textile component in the mixture was the same as in example 1, but the mixture also contained polypropylene oil Κ 1,000 as a modifying additive. This improved its flow properties so much that plasticization on a double-roller took place without any problems - the formation of girdling was fast, the mixture did not fall off the rolls.

The very good flow properties of the mixture are also illustrated by the values of ln M _R3 q, measured on a Brabender plastograph, which are significantly lower than for the mixture according to example 1 and even lower than for the standard mixture:

temperature (°C) 150 160 170 180 ln M _R30 1.29 1.00 , 0.71 0.44

Example 3

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 21.6 polyvinyl chloride suspension K = 60 7.2 dioctyl phthalate 8.8 dibutyl phthalate 1.0 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 36.0 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) _s 0.5 heterogeneous waste s 15.5 % textile components, particle size up to 4 mm 20.0 copolymer vinyl chloride/vinyl acetate-copolymerization ratio (83/17) 3.2

100.0 was prepared (as in the previous examples) by mixing all the components in a fluidized bed mixer. This mixture contained a total of 3.1% by weight of textile component and a vinyl chloride/vinyl acetate copolymer as a modifying additive. The mixture was very well plasticized in a screw mixer and subsequently formed a high-quality girdle on a double roller.

The values of ln M _R3() , measured on a Brabender plastograph, are at the level of the values of the standard mixture:

temperature (°C) 150 160 170 180 ln M _R30 1.57 1.43 1.22 0.96

Example 4

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 20.0 polyvinyl chloride suspension K = 60 6.7 dioctyl phthalate 3.0 dibutyl phthalate 0.3 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 31.8 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) 0.5 heterogeneous waste with 15.9% textile components, particle size up to 4 mm 30.0 vinyl chloride/vinyl acetate copolymer (copolymerization ratio 83/17) 5.0 polypropylene oil Κ 1,000 (mol. wt. 460) 1.0

100.0 was prepared by mixing in a fluidized bed mixer, similarly to examples 1 to 3. The mixture contained a total of 4.8% by weight of textile component and a combination of two modifying additives - vinyl chloride/vinyl acetate copolymer and polypropylene oil Κ 1,000; The combined modifying system used enabled excellent processability of the mixture on a twin-roller.

Rheological measurements on a Brabender plastograph gave the following values ln temperature (°C) 150 160 170 180 ln M _k3() 1.35 1.06 0.79 0.53

Example 5

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 27.0 polyvinyl chloride suspension K = 60 9.0 dioctyl phthalate 8.6 dibutyl phthalate 0.9 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 41.8 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) 0.5 heterogeneous waste with 5% textile component, particle size up to 4 mm 10.0 polypropylene oil Κ 1,000 (mol. wt. 460) 0.5

100.0 was prepared by mixing in a fluid mixer in the same way as in examples 1 to 4. The mixture contained a total of 0.5% by weight of the textile component and, as a modifying additive, polypropylene oil Κ 1 000 in an amount of only 0.5% by weight in the mixture. The mixture was processed very well both in a continuous screw mixer and on a double roller.

Rheological measurements on a Brabender plastograph gave the following results:

temperature (°C) 150 160 170 180 ln M _k30 1.32 1.10 0.90 0.71

Example 6

Mixture composition (amounts of individual components are given in % by weight) polyvinyl chloride emulsion K = 67 21.3 polyvinyl chloride suspension K = 60 7.1 dioctyl phthalate 5.2 dibutyl phthalate 0.6 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 33.6 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.6 lubricant (calcium stearate) 0.4 heterogeneous waste with 18.30% textile components, particle size up to 4 mm 25.0 vinyl chloride/propylene copolymer K = 57-60 4.0 polypropylene oil Κ 1,000 (mol. wt. 400) 1.0

100.0 was prepared by mixing in a fluid mixer in a similar manner as in examples 1 to 5. The mixture contained a total of 4.58 wt. % of textile component and, as a modifying additive, a combination of vinyl chloride/propylene copolymers and polypropylene oil Κ 1,000. The mixture was easy to process and the following ln M _k3Q values were obtained by rheological measurement on a Brabender plastograph:

temperature (°C) 150 160 170 180 ln M _k30 1.49 1.26 1.03 0.82

Example 7

Mixture composition (amounts of individual components are given in weight) polyvinyl chloride emulsion K = 67 24.0 polyvinyl chloride suspension K - 60 8.0 dioctyl phthalate 7.3 micronized limestone, very finely ground, type 10, particle size less than 0.063 mm 40.0 heat stabilizer (dibutyltin mercaptide) 0.2 oleic acid-based surfactant 1.5 lubricant (calcium stearate) 0.5 heterogeneous waste with 9.6% by weight of textile components, particle size up to 4 mm 20.0 vinyl chloride/ethylene vinyl acetate copolymer K = 68 (8% ethylene vinyl acetate) 3.5 polypropylene oil Κ 1,000 (mol. wt. 400) 1.0

100.0 was prepared similarly as in the previous cases by mixing on a fluid mixer. The mixture contained 1.9 wt. % textile component and a combination of modifying additives, consisting of vinyl chloride/ethylene vinyl acetate copolymers and polypropylene oil κ 1000, which enabled excellent processability on a two-roller and subsequently on a four-roller. The following values of ln M _k3Q were obtained by measuring on a Brabender plastograph:

temperature (°C) 150 160 170 180 ln M _fc30 1.46 1.21 0.98 0.75

The choice of a suitable type of modifier depends on the type of heterogeneous waste used, i.e. on the content and type of fibres present in it and on the amount of this waste in the mixture. The influence of the chemical nature of the fibres, their shape and quantity on the resulting rheological behaviour of the mixture is so complex that it cannot be covered by unambiguously defined dependencies. In general terms, it is only true that increasing the content of the textile component in the mixture leads to a deterioration in its flow behaviour and thus also in its processability. In these cases, it is advantageous to choose a combination of both types of modifiers.

Examples 2 to 7 document the effect of the used modifying additives in terms of flow behavior, especially in relation to the processing of polyvinyl chloride mixtures on plasticizing twin-rollers.

The improved flow behavior of these mixtures is not only evident in this phase of their processing, but also positively influences the processability on the four-roller and also the resulting quality of the produced film. This is then reflected primarily in the homogeneity of the film, i.e. in particular in the high degree of dispersion of textile fibers, which is also very favorably reflected in the degree of coloring of the film. There are also no defective areas (holes, unprocessed pieces, etc.) in the resulting film, as is the case with film from the mixture without the addition of modifiers.

The improved processability of mixtures and modifiers in the examples 2 to 7 is mainly related to their plasticization on plasticizing twin-rollers. However, a similar effect can also be observed when a kneader is used as a plasticization unit, e.g. a continuously operating KO type screw kneader. Here, an increase in the kneader performance of up to 10 S was found in direct connection with the processing of mixtures with modifiers.

The basic purpose of the invention is to achieve processability of mixtures with heterogeneous waste by rolling technology into the form of a film that can be used for various product purposes, which determines the requirements placed on it. In the examples, the mixtures were used for the production of one of the flooring films, the so-called central film. The properties of the central film without waste and with waste must be similar enough not to affect the quality of the resulting flooring. The table shows the values of the decisive physical and mechanical parameters of the film without waste and the film with waste from the mixture according to example 4.

Parameter Waste-free foil Foil with waste tensile strength (MPa) along across 10.9 9.5 11.1 8.9 resistance to along 39.7 46.0 to another tear (N/mm) across 33.0 31.7 hardness (°Sh A) 89 87

Subject matter of the invention

Claims (1)

Mixture of plasticized polyvinyl chloride, in particular for sheet-metal products, characterized in that, in addition to the conventional components, in particular emulsion and suspension polyvinyl chloride, plasticizers, stabilizers, lubricants, pigments, fillers and surfactants, it contains 1 to 50% by weight, preferably 3 to 30% by weight of heterogeneous waste based on polyvinyl chloride and / or vinyl chloride copolymers, with an admixture of fibrous material, the resulting content of which in the mixture is 0.1 to 10% by weight, preferably 0.1 to 5% by weight and 1 to 15% by weight, preferably 3 to 10% by weight, copolymers or a mixture of vinyl chloride copolymers and / or 0.1 to 5% by weight, preferably 0.5 to 2% by weight, of a polyolefin oil, e.g. polypropylene oil having a molecular weight of 250 to 600, optionally the same amount of polyolefin oil blend.