摘要:
Free-flowing, stable dispersions of crosslinked rubbers in the form of discrete particles having an average diameter of 0.1 to 3 .mu.m in organic liquids, containingI) up to 60% by weight (based on the dispersion as a whole) of a crosslinked, rubber-like, particulate graft polymer of a) a crosslinked silicone rubber as core and crosslinked acrylate rubber b) graft polymerized thereon as the rubber andII) a liquid, organic N,N-substituted amide as the continuous organic phase,and a process for their production.
摘要:
Copolymers ofa) phosphonic acid derivatives corresponding to formula (I) ##STR1## wherein Y represents H or CH.sub.3,X represents a single bond or --CH.sub.2 --,R represents an aryl or alkyl,b) maleic anhydride andc) a polymerizable compound containing two or more allyl or methally groups in the molecule.
摘要:
Triazolopyrimidines of the formula I ##STR1## in which R.sup.1 denotes CN, alkylsulphonyl, arylsulphonyl or arylR.sup.2 denotes H, alkyl or alkythio,R.sup.3 denotes alkyl, aralkyl, substituted aralkyl, alkenyl or alkynyl,R.sup.4 denotes alkyl, aralkyl or aryl, andR.sup.5 denotes alkyl, aralkyl or aryl, orR.sup.4 and R.sup.5, together with the carbon atom, denote a carbocyclic 5-, 6- or 7-membered ring which may be substituted or bridged,in which R.sup.4 cannot be methyl or aryl when R.sup.1 represents CN, R.sup.2 represents H, R.sup.3 represents methyl and R.sup.5 represents methyl or aryl, and in which alkyl preferably has 1-9 C atoms and aryl preferably has 6-12 C atoms, and also a process for their preparation, and their use as initiators.
摘要:
This invention relates to a process for the graft polymerization of (A) from 95 to 40 parts, by weight, of at least one ethylenically unsaturated monomer in the presence of (B) from 5 to 60 parts, by weight, of a partially or completely cross-linked rubber, in which the one or more than one monomer (A) and rubber (B) in the form of a latex or of a dispersion in an organic solvent are polymerized in an aliphatic hydrocarbon as reaction medium at from 30.degree. to 100.degree. C., using a radical forming initiator, and the graft polymerization product obtained as a sedimenting suspension of particles having an average diameter of from 5 to 1,000 .mu.m is isolated.
摘要:
A thermoplastic moulding composition with improved flow properties being workable without difficulty by extrusion, injection moulding or blow moulding and resulting in colorless, transparent products with a smooth, glossy surface, comprising a mixture of(A)90 to 99.9% by weight of a polymer with a K-value of from 50 to 80, as measured at a temperature of 25.degree. C. in dimethyl formamide on a 0.5% by weight solution, which contains at least 50% by weight of acrylonitrile or methacrylonitrile or a mixture thereof in polymerized or grafted form, and(B)0.1 to 10% by weight of a statistical copolymer of copolymerized units of65 to 85% by weight of at least one acrylic acid alkyl ester with 1 to 8 carbon atoms in the alcohol component, and15 to 35% by weight of styrene,The copolymer B having an intrinsic viscosity [.eta.] of from 2.9 to 13.0 dl/g, as measured at 25.degree. C. in tetrahydrofuran.
摘要:
The invention relates to a process for the continuous production of polyacrylonitrile hydrolyzates and to their use as dispersion and grinding aids for pigments and fillers, such as for example kaolin, CaCO.sub.3 or gypsum.
摘要:
It is possible to remove quantities of heat from exothermically running polymerization reactions of vinyl monomers in heterogeneous phase, in a sophisticated manner by adding liquids to the reaction medium for the removal of heat and to regulate the reaction temperature, which liquids do not dissolve the polymer under the reaction conditions and the boiling temperatures of which are lower than or are identical to the technically predetermined reaction temperatures under the polymerization conditions which are applied, and the heat which is released in the reaction system is removed by evaporating these liquids.
摘要:
Acrylonitrile polymers and copolymers with good affinity for basic dyes without sulfonic acid groups containing comonomers are obtained by polymerizing at a temperature of from 0.degree. to 60.degree. C. in an aliphatic hydrocarbon having a boiling point of from -10.degree. to 80.degree. C. or in a mixture of aliphatic hydrocarbons having boiling points in the range from -10.degree. to 80.degree. C. using an initiator system comprising from 0.1 to 8.0 mole percent of sulfur dioxide, from 0.1 to 2.0 mole percent of a hydroperoxide which is soluble in the reaction medium and from 0.01 to 1.0 mole percent of an acid which is soluble in the reaction system in that polymerization is carried out continuously and in that an average residence time of from 10 minutes to 2 hours is maintained.
摘要:
Vacuole-free films, filaments and fibers consisting of a polymer mixture which comprises a copolymer of acrylonitrile and a polymer which is obtained by a polymer-analogue reaction of a polyacrylic acid ester with dimethylamine, said polymer containing from 40-99 mol % of N,N-dimethyl acrylamide units.
摘要:
Described is a process for producing segmented polyurethanes having improved processing characteristics in the melt state and an efficient spinning process based thereon to form highly elastic, fine linear density elastane yarn and filament having improved mechanical and thermal properties by using hydroxyalkyl-terminated polysiloxanes in combination with specific crosslinking-capable polyisocyanates in the reaction of long-chain high molecular weight polyhydroxy compounds with organic diisocyanates and low molecular weight diols and also optionally further auxiliary and additive substances in the melt.