摘要:
Polyphenylene ethers are prepared from monohydric phenols, which possess alkyl substituents in the two ortho-positions and, if desired, in the meta-position, but not in the para-position, by an oxidative coupling reaction with oxygen at from 15.degree. to 50.degree. C. and under from 1 to 10 bar in the presence of a catalyst complex, of a solvent and, if required, of an activator, by a method in which the conversion of the phenols is carried out in two more reaction zones, in which some or all of the solvent, the catalyst complex and the phenols and, where relevant, the activator is initially taken and is circulated by means of a conveying unit, and about 60-100% of the stoichiometric amount of oxygen required for the oxidative coupling is introduced into the first reaction zone and from 0 to about 40% of the said stoichiometric amount is introduced into the second reaction zone.
摘要:
A process for making ABS polymer particles comprising continuous polymerization of a mixture of at least one of each of (a) an aromatic vinyl monomer, and (b) an ethylenically unsaturated monomer in a weight ratio of (a):(b) of 90:10 to 10:90 in the presence of at least one of each of (c) a rubber-like polymer in an amount of 3 to 35 percent by weight relative to the total weight of the monomers (a) and (b), (d) a solvent, (e) a radical initiator and (f) an optional chain transfer agent. The process is carried out at temperatures between 80.degree. C. to 180.degree. C. in two or more reaction zones while the reaction mixture is stirred and while the monomers and solvents are removed in a degassing zone. The rubber-like polymer (c) has a solution viscosity of less than 80 mPa.s and a ratio of the solution viscosity of (c) to a percent of solvent expressed by 100[(d)/(a+b+c+d)] equal to or less than 2.5 mPa.s/percent of solvent.
摘要翻译:制备ABS聚合物颗粒的方法,包括(a)芳族乙烯基单体和(b)烯属不饱和单体中的至少一种(a):(b)为90的混合物的混合物的连续聚合 在(c)相对于单体(a)和(b)的总重量为3〜35重量%的量的橡胶状聚合物中的至少一种存在下,10〜10:90, (d)溶剂,(e)自由基引发剂和(f)任选的链转移剂。 该方法在两个或更多个反应区中在80℃至180℃的温度下进行,同时搅拌反应混合物,同时在脱气区中除去单体和溶剂。 橡胶状聚合物(c)的溶液粘度小于80mPa.s,溶液粘度(c)与溶剂百分比的比例由100 [(d)/(a + b + c + d)]等于或小于2.5mPa.s /%的溶剂。
摘要:
A process for the continuous preparation of rubber-modified polymers of vinyl-aromatics, wherein a mixture which contains a monomeric aromatic vinyl compound and from 3 to 30% by weight, based on the monomer, of an elastomeric polymer, with or without a solvent, is polymerized, in the presence of a free radical initiator and in the presence or absence of a mercaptan as chain transfer agent, at from 80.degree. to 180.degree. C., with stirring, in a cascade of two or more isothermally operated reaction zones and of one or more additional reaction zones which can be operated isothermally or with a rising temperature profile in such a way that the residence time of the reactants in the first reaction zone is .ltoreq.35 minutes. The polymer obtained is freed from vinyl-aromatic monomer, and from any solvent, in a devolatilization zone. The product is useful for the production of injection moldings.
摘要:
Thermoplastic molding materials based on styrene polymers which have been made impact-resistant and on polyphenylene ethers, wherein the particles of the soft component of the styrene polymer which has been made impact-resistant have a mean diameter of more than 1 micron, and wherein the proportion of particles which have a diameter of less than 0.6 micron is not less than 40% by weight and the proportion of particles which have a diameter of from 0.6 to 3 microns is less than 3% by weight.
摘要:
Thermoplastic molding materials which contain a copolymer which has been made impact-resistant with a rubber. The copolymer is produced by polymerizing a mixture of a monovinyl-aromatic compound and an acrylic acid derivative or methacrylic acid derivative in the presence of a rubber. The folding materials contain a specific proportion of soft component. The diameter of the particles of the soft component, and the swelling index of the soft component, lie within a specific range, and the tensile strength of the molding material is higher than the yield strength.
摘要:
An impact-resistant thermoplastic molding material, containing polystyrene as the matrix, and, dispersed therein, two elastomeric polymers or copolymers I and II composed entirely or predominantly of 1,3-dienes and containing particles of different mean size, namely, in I, particles from 0.2 to 0.6 .mu.m in size and having capsule particle morphology, and, in II, particles from 2 to 8 .mu.m in size, having cell particle or coil particle morphology.
摘要:
A process, carried out without a diluent or in solution, in more than 2 reaction zones, for the continuous preparation of rubber-modified polymers of vinylaromatics, wherein a monomeric aromatic vinyl compound and an elastomeric polymer, in an amount of from 3 to 16% by weight based on the monomer, are polymerized, in the absence of a free radical initiator, but in the presence of a mercaptan as a chain transfer agent, at from 80.degree. to 180.degree. C. in a first reaction zone, with stirring, up to a maximum monomer conversion, U.sub.max, given by the equationU.sub.max =K-1where K is the amount of rubber in % by weight based on monomer, and, in a second reaction zone, polymerization is continued, with stirring, to a conversion of up to about 50% by weight, after which a chain transfer agent is introduced in an amount of from 0.01 to 0.2% by weight, based on vinyl-aromatic monomer, and polymerization is continued, if appropriate in more than one reaction zone, up to a monomer conversion of less than 85% by weight. The polymer is treated in a devolatilization zone to remove vinyl-aromatic monomer and solvent, if any, and these constituents are recycled to the process. The process produces products which exhibit good gloss coupled with good mechanical properties, and which can be employed for conventional applications.
摘要:
Acrylonitrile or monomer mixtures containing acrylonitrile are purified by treating them with alkaline reacting compounds followed by distillation. The products are particularly suitable for the manufacture of acrylonitrile polymers showing improved color stability.
摘要:
An anionically polymerized impact-modified polystyrene has a yield stress of at least 24 MPa, measured at 23° C. to DIN 53455 and a hole impact strength of at least 11 kJ/m2, measured at 23° C. to DIN 53753, measured in each case on a specimen produced to ISO 3167. A preparation process is described.
摘要翻译:阴离子聚合的冲击改性聚苯乙烯具有至少24MPa的屈服应力,在23℃下根据DIN 53455测量,并且在23℃根据DIN 53753测量的孔冲击强度为至少11kJ / m 2,测量 在每种情况下都是根据ISO 3167生产的样品。描述了制备过程。
摘要:
A process for preparing impact-modified styrene polymers (HIPS) omprises anionic polymerization of styrene in the presence of a rubber in one or more polymerization reactors in succession. The rubber is prepared in solution in an immediately upstream process. The heat of polymerization is utilized to remove the solvent for the rubber, this solvent having a boiling point lower than those of styrene and ethylbenzene, from at least one of the polymerization reactors via distillation with distillative cooling, and the solvent is reintroduced into the process of rubber preparation.