DE1268831B - Process for the production of hardened molded bodies - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C08f

German class: 39 b-22/06

Number: 1268 831

File number: P 12 68 831.2-43

Filing date: January 28 , 1960

Open date: May 22 , 1968

The invention relates to a process for the production of hardened moldings on the basis of mixtures of vinyl chloride polymers, polyepoxy compounds, curing agents, in particular Anhydrides of polybasic carboxylic acids, and optionally fillers, dyes, stabilizers and other processing aids.

From German Auslegeschrift 1055 232, French Patent 973,235 and USA. Patent 2,796,413 curable molding compositions of hydroxyl-containing vinyl polymers and dicarboxylic acids or their anhydrides, and carboxyl-containing polyesters or alkyd resins known. It is also known from the "Journal of the American Oil Chemists'Society", 34 (1957), pp. 9 to 11, to use epoxidized fatty acid esters as internal plasticizers for polyvinyl acetate and to crosslink such molding compositions using dibasic acids to form insoluble products.

The invention is based on the object, Ge ao hardened moldings on the above basis with a high content of vinyl chloride manufacture. The solution to this problem is based on the knowledge that vinyl chloride polymers of the following composition:

Method of manufacture
hardened molded body

Applicant:

German Solvay works

Company with limited liability,

5850 Solingen-Ohligs, Keldersstr. 4th

Named as inventor:
Dipl.-Chem. Dr. Gerhard Faerber,
4134 Rheinberg;

Walter Siepmann, 4350 Recklinghausen

5 to 20 percent by weight vinyl alcohol,
3 to 10 percent by weight vinyl acetate,
70 to 92 percent by weight vinyl chloride,

are compatible with polyepoxy compounds and the use of these easily accessible copolymers as a result, it makes it possible to produce molded articles containing considerable amounts of vinyl chloride, with regard to the prior publication in Chem. Soc., a. a. O., surprisingly without the use of a plasticizer.

It is known that low-viscosity epoxy casting resins, for which phthalic anhydride, hexahydro- or tetrahydrophthalic anhydride are used as curing agents, only cure above 100 ° C. at a useful rate without accelerating additives.

The German Auslegeschrift 1 074 261 describes a method for hardening synthetic resins, which may be foamed, based on a mixture of polyepoxy compounds, vinyl chloride polymers and hardeners, in which anhydrides of polybasic carboxylic acids are used as hardeners, which are combined with the polyepoxy compound at least when heating to avoid gelling and subsequent cooling are able to form a mixture which is liquid at room temperature. It has been found that the curing of polyepoxy compounds is significantly accelerated in comparison with this process if a vinyl chloride copolymer containing hydroxyl groups is used.

In some cases, it has proven to be advantageous for the purposes of the invention to use hydroxyl-containing vinyl chloride copolymers which are obtained in a manner known per se by partial hydrolysis from such copolymers which are obtained from vinyl chloride and vinyl acetate by solution polymerization, for. B. in acetone, methanol, chlorinated hydrocarbons or gasoline or have been produced by emulsion polymerization. Hydrolysis products with a vinyl alcohol content significantly exceeding 20 percent by weight are unsuitable for the formation of homogeneous mixtures with polyepoxy compounds because of their incompatibility. When using solvent polymers which have a relatively low molecular weight, epoxy compounds and curing agents result in partly liquid and pourable mixtures, while emulsion polymers form mixtures or pastes with the reactants which can only be shaped by pressing.

The proportions of the reactants can vary within relatively wide limits. The curable compositions preferably contain about 30 to 200 parts by weight of epoxy compounds and about 40 to 80 parts by weight of anhydrides of polybasic carboxylic acids or a mixture of polybasic carboxylic acids and acid anhydrides of polybasic carboxylic acids in a ratio of 1: 2, the parts by weight in each case being based on 100 parts by weight of the vinyl chloride copolymer.

809 550/484

Claims (1)

35 3.75 g of an epoxy casting resin made from epichlorohydrin and diphenylolpropane with an epoxy equivalent weight of 198.3 were added together with 2.5 g of hexahydrophthalic anhydride and 3.75 g of a copolymer, the content of which was vinyl alcohol at 18% by weight, vinyl acetate at 3% by weight and vinyl chloride was determined to be 79 percent by weight and which has not yet hardened from a solution polymer of vinyl alcohol and vinyl chloride by quenching even after 120 hours at 95 ° C. with alcoholic hydrogen chloride. Example 5 was melted by careful heating. A homogeneous melt was formed. This was poured into a prepared mold onto 21 g of a hydrolyzed copolymer with a cellulose film. The curing temperature 45 13.5 percent by weight vinyl alcohol, 6 percent by weight 95 ° C. After 16 hours, a black vinyl acetate and 80.5 percent by weight vinyl, a hard, shiny body had formed, the Vicat chloride, which is obtained from an emulsion polymerization value of 91 ° C., Martens degree 65.degree. C. and Shore hardness (D), the intermediate product obtained by alcoholysis was 82. 10 g of hexahydro- Was the ratio of epoxy resin to mixed poly- 50 phthalic anhydride and 9 g of ethylene glycol diglycide- A mixture of 3.75 g of the casting resin used in the example, 3.75 g of the copolymer used in the example and 2.5 g a mixture of 65 percent by weight of phthalic anhydride and 35 percent by weight of phthalic acid was heated for 18 hours at 95 ° C. in a mold lined with cellulose film. The brown-black glossy crosslinked body formed had a Vicat value of 76 ° C. and a Shore half (D) of 84. If the same amount of casting resin was used instead of the copolymer, this amount was increased to 2: 1 and a mixture Cured from 5 g of the epoxy resin and 2.5 g of the copolymer with 2.5 g of hexahydrophthalic anhydride at 95 ° C., the Vicatt temperature was 67 ° C. after 16 hours (2.5 g) passed, at the same curing temperatures at least 24 hours thin. EXAMPLE 2 3.75 g of the casting resin used in the example and 3.75 g of the vinyl alcohol-vinyl acetate-vinyl chloride copolymer from this example were melted together with 2.5 g of tetrahydrophthalic anhydride and poured into the mold lined with cellulose film. After a curing time of 65 hours at 95 ° C, a hard brown-black 55 60 ether was mixed in a blender. The powder obtained was pressed for 30 minutes at 130 ° C. with 70 kg cnra to form a 2.5 mm thick plate. A transparent, light brown disc was obtained which was completely insoluble. You couldn't scratch the surface with your fingernail. When using 7 g of diglycidyl ether instead of 9 g of ethylene glycol diglycidyl ether, a plate with similar properties was obtained. Patent claims: 1. Process for the production of hardened moldings on the basis of mixtures Vinyl chloride polymers, polyepoxy compounds, hardeners, especially anhydrides polybasic carboxylic acids, and optionally fillers, dyes, stabilizers and further processing aids, thereby