摘要:
A process for the manufacture of high impact and translucent polystyrene, in which, in a first stage, styrene is prepolymerized in mass or in solution in the presence of a rubber, and the polymerization is then completed in mass, in solution or in aqueous suspension. The prepolymerization is taken to a stage where the amount of styrene converted is from 3 to 10 times the amount of the elastomer constituent of the rubber, and at this conversion the disperse soft-component phase formed should have a mean particle size of less than 1 .mu.m and should contain from 35 to 65% by weight of free or chemically bonded polystyrene segments. The translucent styrene polymers of high impact strength may be used for packaging purposes.
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:
A thermoplastic molding material contains, in each case based on the molding material comprising A+B,A from 80 to 60% by weight of a hard matrix composed of polystyrene andB from 20 to 40% by weight of a soft phase which is obtainable by polymerization of styrene in the presence of a linear styrene/butadienne block copolymer which has an ill defined transition, contains from 35 to 45% by weight of styrene and from 65 to 55% by weight of butadiene and has a block polystyrene content of from 25 to 35% by weight, the soft phase being uniformly distributed in the hard matrix and having a particle diameter of less than 0.8 .mu.m.The typical features of the said molding material are that the median particle diameter d.sub.50 (volume average of the soft phase B is from 0.25 to 0.38 .mu.m, the width of the particle size distribution, (d.sub.95 14 d.sub.5), is from 0.2 to 0.6 .mu.m, the d.sub.60 value is from 0.26 to 0.40 .mu.m and the d.sub.90 value is from 0.40 to 0.75.
摘要:
The catalyst is removed in the preparation of high molecular weight polyphenylene ethers from monohydric phenols, which are alkyl-substituted at the two ortho-positions but not at the para-position and may or may not be alkyl-substituted at the meta-position, by an oxidative coupling reaction with oxygen at from 15.degree. to 50.degree. C. in the presence of a catalyst complex obtained from a copper salt and an organic amine, in the presence of from 1 to 20 parts by weight of a solvent per part by weight of the monomeric phenol, and in the presence or absence of an activator, and removal of the metal component of the catalyst from the polyphenylene ether solution with a complex-forming or chelate-forming compound in aqueous solution, in the presence or absence of reducing and stabilizing substances and assistants for accelerating the interphase reactions and for phase separation, by a method in which the continuous removal of the copper catalyst is carried out in one or more mixer-settler stages at a phase volume ratio of the organic phase to the aqueous phase of from 1:0.1 to 1:1.0, preferably from 1:0.4 to 1:0.6.
摘要:
A thermoplastic molding material consists of from 10 to 90 parts by weight of a polycarbonate A and from 90 to 10 parts by weight of a graft copolymer B having a mean particle size of from 200 to 700 nm (d.sub.50 value of the integral mass distribution). The graft polymer B is formed from an elastomer (rubber) (b.sub.1), which accounts for from 10 to 80% by weight, and a grafted shell (b.sub.2), which accounts for from 90 to 20% by weight, the percentages in each case being based on (B).The elastomer (b.sub.1) is composed of from 50 to 99.9% by weight of an alkyl acrylate, where alkyl is of 1 to 8 carbon atoms, and from 0.1 to 5% by weight of a copolymerizable polyfunctional crosslinking monomer.The grafted shell (b.sub.2) is produced in three stages and contains, as graft monomers,(b.sub.2 a.sub.1) from 5 to 40% by weight of a monoethylenically unsaturated aromatic hydrocarbon of not more than 12 carbon atoms, in the first stage,(b.sub.2 a.sub.2) from 15 to 50% by weight of a mixture of a monoethylenically unsaturated aromatic hydrocarbon of not more than 12 carbon atoms and a copolymerizable ethylenically unsaturated monomer, in a weight ratio of from 90:10 to 60:40, in the second stage, and(b.sub.2 a.sub.3) from 10 to 85% by weight of an alkyl (meth)acrylate in the third stage, the percentages in each case being based on (b.sub.2).
摘要:
The use of tricyclodecenyl alcohol in place of other crosslinking agents for crosslinking the soft component of impact-resistant polystyrene based on a polystyrene-grafted poly(alkyl acrylate) improves the flow of mixtures of the said polystyrene with polyphenylene ethers.
摘要:
Molding materials comprising a matrix of high impact polystyrene and rubber incorporated in the form of discrete particles contain not less than 50% by weight of polystyrene A and an effective amount of up to 50% by weight of a graft rubber B. The graft rubber B consists of from 40 to 95% by weight of an elastomeric core b.sub.1 and from 5 to 60% by weight of a shell b.sub.2, i.e. from 5 to 50% by weight of a first shell B.sub.21 of styrene and from 50 to 95% by weight of a second shell b.sub.22 of from 60 to 90% by weight of styrene and from 10 to 40% by weight of acrylonitrile, A and B, b.sub.1 and b.sub.2, b.sub.21 and b.sub.22 and styrene and acrylonitrile each summing to 100% by weight.
摘要:
Impact modified thermoplastic blends of components A, B and optionally C, consisting of:A) from 99 to 60 percent by weight of a polymeric rigid matrix consisting ofa1) 60-99.5 percent by weight of an aromatic vinyl compound present as copolymerized units,a2) 0.5-20 percent by weight of an unsaturated carboxylic anhydride present as copolymerized units anda3) 014 35 percent by weight of an alkenylnitrile present as copolymerized units,B) from 1 to 40 percent by weight of a polymeric flexibilizing component consisting ofb1) 100-60 percent by weight of a monomer from the group of the 1,4-dienes which is present as copolymerized units andb2) 0-40 percent by weight of an aromatic vinyl compound present as copolymerized units. and optionallyC) customary additives in customary amounts, the polymers of flexibilizing component B having amino end groups, are used for producing moldings.
摘要:
Impact resistant thermoplastic molding materials containing a styrene polymer modified with rubber to be impact resistant, a hydrogenated styrene containing block copolymer and a polyphenylene ether as well as optional additives in which 50 to 98 percent by weight of the particles of the flexible component of the impact resistant styrene polymer have an average particle diameter of equal to or less than 1.0 micron and 2 to 50 percent by weight of the particles of the flexible have an average particle diameter of equal to or greater than 2 microns.
摘要:
A flameproofed thermoplastic molding material consists ofA. a thermoplastic resin containing a vinylaromatic monomerand furthermore containsB. from 0 to 100 parts by weight of an elastomer having a glass transition temperature Tg 0.degree. C., as an impact modifier,C. from 2 to 50 parts by weight of a halogen-containing organic compound (flameproofing agent),D. from 0.5 to 20 parts by weight of a compound containing a metal or non-metal (synergistic agent) andE. from 5 to 50 parts by weight of a novolak (phenol/aldehyde resin).The novolak is obtained from an aldehyde of the formula (I)R.sup.1 --CHO (I)where R.sup.1 is H, C.sub.1 -C.sub.10 -alkyl, cycloalkyl, C.sub.6 -C.sub.12 -aryl or .omega.-aryl-C.sub.1 -C.sub.3 -alkyl, and a mixture of phenols, and this mixture contains two or more monosubstituted phenols and the substituents can be alkyl of 1 to 8 carbon atoms or CN.The molding material is used for the production of flameproofed moldings.