摘要:
Anionic polymerization is used for the preparation of reaction mixtures comprising homopolymers, copolymers or block copolymers, and of homopolymers, copolymers and block copolymers which comprise acrylates or methacrylates or acrylates and methacrylates, wherein olefinically unsaturated compounds which are not acrylate or methacrylate derivatives are employed as solvent or as solvent component.
摘要:
Preparation of rubber-modified molding compositions comprises a1) anionic polymerization of a mixture (A) comprising acrylate derivatives or methacrylate derivatives or acrylate derivatives and methacrylate derivatives and a solvent, if desired comprising olefinically unsaturated compounds which are not an acrylate derivative or a methacrylate derivative, or a2) sequential anionic polymerization of acrylate derivatives or methacrylate derivatives or acrylate derivatives and methacrylate derivatives in the presence of a solvent which, if desired, comprises olefinically unsaturated compounds to give block copolymers, and b) subjecting the reaction mixture obtained in a1) or a2) or a1) and a2) to a free-radical-initiated polymerization, if desired after the addition of unsaturated compounds.
摘要:
A process for preparing a solution of high molecular weight polymers of conjugated dienes in a vinylaromatic hydrocarbon by anionic polymerization of the diene in the presence of an alkyllithium as catalyst and a process for preparing impact-modified polymers of vinylaromatic compounds is described. The first process comprises firstly polymerizing the diene in solution in an aromatic hydrocarbon which is free of ethylenic double bonds to a molecular weight below about 105, then adding a trialkylaluminum in a molar excess relative to the alkyllithium, diluting the solution obtained with the vinylaromatic compound and then coupling the polydiene with a polyepoxide or an alkyl (meth)acrylate to give a high molecular weight polymer. The solution obtained in this way is further processed to give an impact-modified polymer of a vinylaromatic hydrocarbon by polymerizing the solution prepared as described, if desired after addition of further amounts of a vinylaromatic compound, in a manner known per se.
摘要:
Disclosed are a process for the preparation of an initiator composition comprising an alkali metal organyl and an aluminum organyl and a process for the polymerization of anionically polymerizable monomers.
摘要:
In a process for polymerizing dienes in a solvent comprising vinylaromatic monomers, the polymerization is carried out in the presence of a metal compound of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo or W as catalyst and a Lewis acid as cocatalyst and, if desired, an alkylating agent and, if desired, a regulator. This process can be used for preparing high-impact polystyrene, acrylonitrile-butadiene-styrene copolymers or methyl methacrylate-butadiene-styrene copolymers.
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:
In a process for the preparation of block copolymers from vinylaromatic monomers and dienes, the monomers are polymerized in the presence of at least one alkali metal organyl or alkali metal alkoxide and at least one magnesium, aluminum or zinc organyl.
摘要:
In a process for the homopolymerization of vinylaromatic monomers or the copolymerization of vinylaromatic monomers and dienes in the presence of at least one alkali metal compound and at least one compound of an element of group 3a of the Periodic Table of the elements, the compounds contain, based on the sum of molar equivalents of alkali metal and elements of group 3a, in each case a) from 0.1 to 3.9 molar equivalents of oxygen, sulfur, nitrogen or phosphorus and b) from 0.1 to 3.9 molar equivalents of an organyl ligand.
摘要:
In a process for the homopolymerization of vinylaromatic monomers or the copolymerization of vinylaromatic monomers and dienes, the monomers are polymerized in the presence of at least one alkali metal organyl, at least one magnesium organyl and at least one aluminum organyl. The invention also provides an initiator composition for carrying out the process.
摘要:
The anionic polymerization of dienes or copolymers of dienes and vinylaromatic monomers in a vinylaromatic monomer or monomer mixture to give homopolydienes or copolymers or mixed homopolydienes and copolymers is carried out in the presence of a metal alkyl or aryl of an element having a valence of at least two without addition of Lewis bases.