CS201491B1 - Composition for pastes based on polyvinyl chloride or copolymers of vinyl chloride - Google Patents

Description

^; The present invention relates to a paste composition based on polyvinyl chloride or vinyl chloride copolymers comprising a polymer and a plasticizer. . In the preparation of pastes based on polyvinyl chloride or vinyl chloride copolymers, the process of solvation or swelling takes place after mixing the basic components, i.e. the polymer and the plasticizer. On average, the plasticizer gradually penetrates into the polymer particles, whereby first the secondary polymer particles formed by aggregation of the primary latex particles upon drying occur. In the next stage, the solvation of the primary particles takes place, the degree of which only determines the quality of the paste and its applicability for further processing.

The speed of the solvation process is influenced by a number of factors such as plasticizer quality, secondary particle size and surface skin hardness, amount and type of emulsifier on the particles, and the method of paste preparation. However, the decisive factors are the hardness and particle size of the polyvinyl chloride powder secondary particles. The speed of the solvation process and thus of the secondary particle decomposition process is generally low. Depending on the above factors, disintegration occurs in the range of several hours to several days.

To speed up the solvation process, several ways are known:

291491

1) use of faster solvating plasticizers

2) use of preheated plasticizers

3) heating the paste during the mixing process

4) higher mixing intensity of the paste

5) repainting the trap on three-rollers.

Of these methods, the use of faster solvating plasticizers is still effective in practice despite some effect on process speed. Methods based on adjusting the mixing conditions (heating of plasticizers or directly formed paste, possibly higher mixing speed) are highly sensitive to the precise choice of conditions. With a slight deviation, gelation and thus degradation of the paste can already occur during mixing. The disadvantage of overcoating the paste is the necessity to use an additional device and thus to include another working operation.

The disadvantages of the known methods of accelerating the solvation of polyvinyl chloride and its copolymers are overcome by the use of the compositions according to the invention which contain, as an effective activator of secondary particle decomposition, 0.1 to 10 parts by weight per 100 parts of paste. alcohols having from 1 to 4 carbon atoms in the chain, ketones and ethers of the general formulas R1. CO. Ø2 and Ri, respectively. OR 2, wherein R 1 and R 2 are alkyl of 1 to 5 carbon atoms, acetic acid esters of the formula CH 3. COOR wherein R is alkyl or alkoxy. C1-C5-xyl, up to 6-membered O-chain heterocyclic compounds, aliphatic hydrocarbons of up to 10 carbon atoms in the chain, dirylformamide, monoethanolamine and monosubstituted benzene derivatives of 1 to 3 carbon atoms in the aliphatic or olefinic chain.

The use of compositions with activators of the solvation process of this invention greatly accelerates paste technology, allows omission of paste overcoating and reduces viscosity. Another important benefit is the possibility of preparing and using pastes with a higher content of coarser, larger particles. Until now, polymers of this type have not been used for colored coverings of leatherette and floor coverings, because the slow solvation of coarser particles has resulted in color changes. Finally, another important benefit of solvation activators is that they make it possible to prepare both paste and emulsion type polymers that cannot be processed into pastes by prior art processes.

To further elucidate the subject matter of the invention, mixtures containing 60 wt. 39 parts by weight of dioctyl phthalate and 1 part by weight of the activator. The mixtures were mixed in a beaker for 10 minutes, after measuring ^. ''·> ”· · · ··· · · i. ¹ >

no solvation number, according to the technical acceptance conditions for domestic paste-forming polyvinyl chloride: the paste prepared on a filter paper on a glass substrate is applied to a circular surface of 10 mm diameter and left to temper for 1 hour at 25 ° C. After this time, the diameter of the stain on the filter paper is measured in two mutually perpendicular directions. The solvation number, t (jprn2) is the product of both measured diameters. The apparent viscosity of the paste is measured after 15 mih '. by tempering at 25 ° C at a rate of 4.5 s ^1-1 '. ;

The effect of the individual solvation activators is illustrated in the table:

Table

Číš. activator solvation viscosity (mPa.s) '- ·' shovel. number (mm ² ) 1 without activator 41 200 290 ' 2, ethanol. 23 200 ' . . · ₁₆ o · 3. acetrai 19 600 130 4 ’ ethyl acetate 17 500 160 5 ethyl ether 25 600 170 6 dioxane 16100 140 7 dimethylformamide 15 000 135 8 n-heptane 36 000 -145- 9 styrene 16 200 220 ; , X0 " _{ethanolamine,! WITH} 16 000 150

THE OBJECT OF THE INVENTION

Claims (1)

Mixture for pastes. vinyl chloride-based polymers or vinyl chloride copolyers containing a polymer and a plasticizer; characterized in that it contains, as an activator of the decomposition of secondary polymer particles in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the paste, a substance or a combination of substances from the group comprising alcohols having 1 to 4 carbon atoms in the chain; formulas. Rt. CO. Rz and Ri, respectively. O, R 2, wherein: R 1 and R 2 are alkyl groups of 1 to 5 carbon atoms, esters of acetic acid of the common yeast. CHis. COOR, 'who. R 6 is an alkyl or alkoxy group having 1 to 5 carbon atoms, 5 to 6 membered hetero, cyclic compounds with oxygen γ. chain, aliphatic, hydrocarbons having 6 to 10 carbon atoms in the chain, dimethyl formamide, monoethanol and monosubstituted benzene derivatives having 1 to 3 carbon atoms in the aliphatic or olefinic chain.