DE1544803B2 - Molding compounds based on tactical homo- or copolymers of vinyl chloride - Google Patents

Description

2. Molding compositions according to claim 1, characterized in that that the vinyl acetate-ethylene copolymers are crosslinked and have a degree of crosslinking between 10 and 40.

It is known to improve the mechanical properties of tactical polyvinyl chloride by adding to improve chlorinated atactic polyvinyl chloride; see Belgian patent specification 626 843. Products from Molding compounds on this basis are characterized by high dimensional stability under heat and by improved mechanical values compared to those made from pure tactical polyvinyl chloride are sufficient, however For example, the U-notch toughness is not sufficient for certain applications.

It is also known to use atactic polyvinyl chloride with high molecular weight compounds such as chlorinated To elasticize polyethylene, which here gives optimal values for U-notch toughness; Farther come butadiene polymers, copolymers and graft polymers, polyurethanes and copolymers from ethylene and vinyl acetate or ethylene and acrylic acid esters as elasticizing agents for Use.

As can already be seen from the Belgian patent specification 626 843, attempts were made to also use molding compounds on the Based on tactical polyvinyl chloride with butadiene copolymers and chlorinated polyethylene, but these additives were not analogous Effectiveness as with atactic polyvinyl chloride.

It has now been found that, of the abovementioned elasticizing components, mixed polymers of vinyl acetate with ethylene added to the tactical polyvinyl chloride give molding compositions with particularly high U-notch toughness with regard to the products made from them at a hardly reduced Vicat temperature. In comparison with corresponding moldings made from atactic polyvinyl chloride, surprisingly, the U-notch toughness values are even higher, although it must process these molding compositions at temperatures between 190 and 21O ⁰ C, for generally fall namely the U-notch toughness with increasing processing temperature. As Examples 9 and 10 show, the U-notch toughness of a test plate made of atactic polyvinyl chloride with 5 parts of a copolymer of vinyl acetate and ethylene at 190 to 210 ° C processing temperature is 5.4, at 170 to 180 ° C processing temperature 8.8 cmkp / cm ² . The test panel analogously prepared at 190 to 210 ⁰ C of tactic polyvinyl chloride is a U-notch toughness, which is still far above the ⁰ to 180 C processed test plate of atactic polyvinyl chloride, according to Example 7. FIG.

The copolymers of vinyl acetate and ethylene used for elasticization should have a vinyl acetate content of 30 to 70 percent by weight and a relative viscosity (1% in chloroform) between 1.8 and 6.5. The copolymers can also be crosslinked, the degrees of crosslinking being between 10 and 40, determined by the chloroform uptake in grams per gram of polymer after storage at 20 ^° C. in chloroform for 24 hours. Molding compounds made from tactical polyvinyl chloride and cross-linked! Mixed polymers made from vinyl acetate-ethylene are also characterized by increased chemical resistance. The content of copolymers of vinyl acetate-ethylene in the molding compounds is between 0.5 and 10 percent by weight, based on the polyvinyl chloride.

A polymer is called tactical polyvinyl chloride, the chlorine atoms of which are about 55 to 85% are arranged syndiotactically. Tactical polyvinyl chloride can be produced by various processes, see for example DAS 1 187 374, Belgian patent 627 674 and British patents 895 153 and 931 629.

To characterize tactical polyvinyl chloride, in addition to the radiographic examination The dimensional stability under heat according to Vicat (VDE 0302 Paragraph 7b) is also used will. The Vicat values of tactical polyvinyl chloride are 10 to 15 ° C above those of the atactic polyvinyl chloride. In addition to the tactical homopolymers of vinyl chloride, tactical Copolymers of vinyl chloride with comonomers between 0.5 and 20 percent by weight, such as Ethylene, propylene, vinyl acetate, acrylic acid ester, dichloroethylene and the like with the Copolymers of vinyl acetate and ethylene are elasticized according to the invention. In addition to these Components, the molding compounds can contain other high polymers, such as chlorinated polyvinyl chloride, polyethylene, Polypropylene, polysobutylene, polyvinyl acetate, polyacrylonitrile, polyvinyl ether and the like, as well as Contain stabilizers, lubricants, fillers, etc.

example 1

100 parts of tactical polyvinyl chloride (q _rel 2.8) are mixed with 1.5 parts of a tin stabilizer of the formula (nC ₄ H ₉ ) ₂ Sn (S —CH ₂ COOC ₈ H ₁₂ ) ₂ and 0.5 part of a montan wax as a lubricant at 19O ⁰ C rolled and ^{pressed at 210 0} C to form a test plate.

Examples 2 to 8

Under the conditions given in Example 1

5 parts of the elasticizing component are also incorporated into the approach on the roller.

Here, chlorinated polyethylene with a chlorine content were used as elasticizing components in Example 2 of 40.2 percent by weight; in example 3 a chlorinated polyethylene with a chlorine content of 39.8 percent by weight; in example 4 a polyester urethane produced from 1,4-butanediol adipic acid ester (Hydroxyl number 100) and free butanediol (hydroxyl number 200), hardened with diphenylmethane-pp'-di-

isocyanate; in Example 5 a copolymer of ethylene and ethyl acrylate (ethylene content 72 percent by weight); in Example 6 a graft polymer prepared from 50 percent by weight of methyl methacrylate 50 percent by weight of a styrene-butadiene copolymer (60 percent by weight styrene); in example 7 a solid copolymer of vinyl acetate and ethylene with 45 percent by weight vinyl acetate; in example 8 crosslinked copolymer, which from the copolymer of Example 7 by crosslinking to a Crosslinking degree of 30 was used.

Example!)

Instead of 100 parts of tactical polyvinyl chloride - as in Example 7 - 100 parts of tactical polyvinyl chloride are used Polyvinyl chloride used. The copolymer: is that of Example 7.

B e i s ρ i e 1 10

As in Example 9, but processing takes place on the roller at 170 ° C. and on the press at 180 ° C. The table below shows the results.

Elasticizing component

Tensile strength (kp / cm ² ) elongation

U-notch (cmkp / cm ² )

Vica t

2. 5 parts of chlorinated polyethylene

3. 5 parts of chlorinated polyethylene

4. 5 parts of polyurethane

5. 5 parts of copolym. Ethylene-ethyl acrylate

6. 5 parts of graft. Butadiene styrene methyl

methacrylate

7. 5 parts of copolym. Vinyl acetate-ethylene

8. 5 parts of copolym. Vinyl acetate-ethylene cross-linked.

9. 5 parts of copolym. Vinyl acetate-ethylene

10. 5 parts of Copolym. Vinyl acetate-ethylene

645
550
525
645
530

595
555
575
510
520

55
60
8th
21
27

28
40
55
85

3.1 4.9 5.4 2.0 5.2

3.6

17.0

16.0

5.4

8.8

91

88 87 88 88

91 89 89 .79 79

Claims (1)

Patent claims: 1. Thermoplastic molding compounds, consisting of A) 90 to 99.5 percent by weight tactical homo- or copolymers of vinyl chloride and B) 0.5 to 10 percent by weight copolymers of vinyl acetate and ethylene, their Vinyl acetate content between 30 and 70% and its relative viscosity (1% in chloroform) between 1.8 and 6.5.