SU560891A1 - The method of obtaining turbid materials - Google Patents

Description

one

The invention relates to the production of opaque opaque materials based on acrylates, which can be used both in the lighting industry and in construction as decorative and decorative materials.

Known methods for producing opaque materials are based on the introduction of polymers, inorganic compounds or inorganic compounds and polymers together into a polymerization reaction system based on acrylates l. A method is known, for example, for producing turbid materials by the polymerization of methymetmetacripate (MMA) in the presence of a copolymer of ethylene and vinyl acetate and titanium oxide 2.

A mixture of a copolymer of trifluorochloroethylene with binipide fluoride and barium sulphate is proposed as a mutant in the preparation of lighting engineering glass based on methyl methacrylate h.

In some cases, with the aim of creating matte screens, it is proposed during the polymerization

MMA introduces metal oxides (TiO, ZtiO, Co O), carbonates Zt7, Pt, Ca,; sulfoxides, aluminates, silicates of Cu, Mg- and tm. four.

All known methods have the following disadvantages.

Firstly, it is difficult to prepare homogeneous, resistant to sedimentation and coagulation, cisperse indication of additives in the monomer. Therefore, stringent requirements are imposed on the particles to be dispersed in terms of particle size and lyophilicity (the surface of pigment particles, better than TiO, is pre-hydrophobized; and another method for stabilizing suspensions is achieved by mashing the pigment with molecular weight less than 31O in the presence of soap fatty acids. Sometimes special mixers are used to obtain a uniform dispersion.

Secondly, the sedimentation of dispersible particles during the polymerization of monomers leads to the production of materials that are heterogeneous in both physical and mechanical properties, and to a greater degree in their lighting characteristics. Creating a high polymerization rate allows this drawback to be avoided to some extent. B. Thirdly, the difficulty (and sometimes even the impossibility) of filtering the reaction see from foreign impurities: (dirt, applied together with the addition of pigments; sinter, melted particles of dispersible (polymers) leads not only to the poor appearance of the turbid sheets, but also to the deterioration of the physicomechanical properties caused by the uneven polymerization rate on the surface of the material. A known method for producing opaque materials by polymerizing MML in the presence of polyvinyl chloride (PVC), which is Aamutnitpem, a polymerization initiator and a stabilizing additive, cimetacrine ester of diphenylopropane, Coll., a stabilizing additive is introduced into the monomer mixture in the amount of 2-2 and weight by 1OO weight, including MMA, in order to increase the heat resistance of the material and to maintain good lighting properties after UV irradiation. The method of obtaining 5. turbid keters is the complexity of the technological process, due to the need to choose a polymer (PVC) with a certain degree of dispersion and wettability powdered particles thereof, thoroughly mixing PVC with MMA, sedimentation of the Polymer during the extrusion of the reaction mixture, and in the process of further polymerization. Sedimentation degrades both the physicomechanical and the lighting properties of the material. In addition, the heat resistance of the resulting material is low. The purpose of the invention is to simplify the process of obtaining clouded materials and increase heat resistance while maintaining good lighting properties and specific toughness after UV irradiation. According to the invention, the goal is achieved in that the dimethacrylates or bisphenol diacrylates are introduced in the forpolymer of methacrylic ester or in their mixture with the esters of acrylic acid. As dimethacrylates and diacryl-TOR bisphenols, shell compounds are used (C-C-0-R-0-C-C-CH.J, Ki, H, CH) yurmyls. The method is carried out as follows. During the polymerization of the starting mixture, methyl methacrylate copolymers are formed and acrylic and methacrylic acid esters and polymers of acrylic and methacrylic acid esters, which combine to a limited extent with poly (methyl methacrylate) prepolymer. The degree of turbidity is due to their incompatibility, which depends on the molecular weight of the polymer in the prepolymer, conv of the prepolymer ratio, the ratio of the prepolymer and esters in the initial reaction mixture and the temperature of the polymerization process. Good homogeneity and high degree of dispersion is achieved by the fact that during the polymerization process a homogeneous transparent reaction mixture (compatible system) turns into an opaque, cloudy material (limited the system is compatible) i.e. the dispersion occurs at the macromolar eclectic level. The amount of esters introduced is from 5 to 20 parts by weight. per 100 weight parts prepopimer. The proposed method, in comparison with the known ones, provides high quality of material turbidization due to the dispersion of macromolecules at a real level. In addition, the introduction of esters of acrylic and methacrylic acids increases the heat resistance and stability to UV irradiation of the resulting lighting material. The method allows to obtain lighting products by reaction molding in a mold under pressure from 10 to 20OO kg s / cm and at a temperature from 5O to 2OO ° C. If it is necessary to obtain materials of 5-6 lighting groups, it is possible to introduce various inorganic pigments, while their sedimentation is eliminated due to the fact that the original mixture can be prepared with the necessary viscosity. Example 1. K 1OO weight.h. Methyl methacrylate prepolymer (conversion 4 O%, molecular weight of polymer 8OOOO), 10 weight parts are added. diphenylolpropane dimethacrylic ester. The reaction mixture is poured into a stainless steel mold. The polymerization is carried out at a temperature of 140 s for 20 minutes. A clouded material is obtained, the properties of which are given in the table.

Example 2. To SHO vys.ch. foripolymer of methyptacripate and methyl acrylate (methlacrylate in the amount of 2.0% by weight of MMA; conversion of the prepolymer to 31%, molecular weight 1OOOOO) was added 5 parts by weight. dimethacrylic ester of dif-nilolpropane, the reaction mixture is poured into a silicate glass mold and polymerized in two stages: the first stage temperature is 50 ° C, the polymerization time is up to readiness; the temperature of the second stage, the polymerization time is 1 hour.

The properties of the turbid material are shown in the table.

Example Z.K 1OO weight.h. Methymethacrylate prepolymer (convert 28%, molecular weight 110,000) add 10 weight parts of diphenipopropane dimethacry ester. The polymerization was carried out as described in Example 2.

Properties of the material obtained are shown in the table.

Example 4. K 1OO weight.h. the prepolymer of methyl methacrylate and methyl acrylate (methyl acryl at 2% by weight of MMA; conversion of the prepolymer to 31%, molecular weight 1OOOOO) was added 15 parts by weight. diphenylolpropane dimethacrylic ester. The polymerization was carried out as described in Example 2.

Properties of the material obtained are shown in the table.

Example 5. To 100 weight.h. Methyl methacrylate prepolymer and butyl acrylate (butyl acrylate O wt.% MMA; conversion of prepolymer 22%, molecular weight 76OOO, 7 weight parts of dimethacrylic ester of hydroquinone is added. The polymerization is carried out as described in Example 2.

Properties of the material obtained are given in the table.

EXAMPLE 6 To 10 parts by weight of a prepolymer of methyl methacrylate in butyl acrylate (butyl acrylate 10% by weight of MMA; conversion of the prepolymer to 22%, molecular sec 76OOO, 8 parts by weight of hydroquinone diacrylic ester are added. Polymerization is carried out as described in example 2.

Properties of the scaled material are listed in the table.

The introduction of dimethacrylates and dnacrylates

Bisfengol in Forpolimer significantly simplifies the process of obtaining turbid materials, since there are no stages of mixing with PVC, sedimentation of the mixture and a stage of introducing other additives. The introduction of these additives in the precolkmer makes it possible to significantly increase the heat resistance and to obtain a material with good lighting properties and a good toughness after UV irradiation.

Example 7. To 100 weight.h. methyl methacrylate prepolymer (conversion 23%, molecular weight of 13OOOO polymer) 20 parts by weight are added. Diphenylolpropane dimethacrylic ester. The reaction mixture is poured into a silicate glass mold and polymerized in two stages: temperature of the first stage, time of polymerization until ready; the temperature of the second stage is 115 ° C, the polymerization time is 1.5 h.

The properties of the turbid material are shown in the table.

Example 8. K 1OO weight.h. the prepolymer of methyl methacrylate and butyl acrylate (butyl acrylate in the amount of 10.0 wt.% of MMA; conversion of the prepolymer to 25%, molecular weight 9OOOO) was added 2% by weight. dimethacrylic ester of hydroquinone. The polymerization is carried out as described in Example 1. The properties of the material obtained are listed in the table.

Example 9. K 10O weight.h. the prepolymer of methyl methacrylate and methyl acrylate (methyl acrylate in the amount of 5 wt.% of MMA} onverse of the prepolymer 34%, molecular weight 11OOOO) is added 2 of the weight parts. hydroquinone diacrylic ester. The polymerization is carried out as described in Example 1.

Claims (6)

The properties of the material obtained are given in the table. The method of obtaining clouded materials by copolymerization of methacrylic acid esters or a mixture of methacrylic and acrylic esters with dimetic acrylates or bisphenol diacrylates of general formula H t CC -O-AND-C-C CH CH KH.CHj) in an amount of 5-20% by weight Monomeroa, characterized in that, with the entirety of the complex, the simplification of the process and the increase in heat resistance of the material while maintaining good lighting properties and specific impact strength after UV irradiation, bisphenol diacrylates or inaccuracy is applied Methacrylic acid or mixtures thereof with acrylic esters. Sources of information taken into account during the examination: 1. Author's certificate No. 219174, cl. C O8 i 29/46, 1968 2. Japanese Patent No. 16848/68. 3. The author's certificate number 181276, cl. C 08 f 29/46, 1966 4.UK patent number 1080549, cl. SED, 1968 5. The copyright certificate M 35394O, cl. C 08 f 25 / GS, 1972 6. Copyright certificate № 423357, C O8 29/46, C O8 1 29/18, 1974 (prototype).