摘要:
High molecular weight aromatic polycarbonates having molecular weights M.sub.w (weight average) of between about 10,000 and 200,000, which are based on diphenols and monofunctional chain stoppers, which correspond to the general formula ##STR1## in which Z denotes the radical of a diphenol,n denotes an integer from 20 to 400,E denotes ##STR2## m is 0 or 1 and R denotes a hydrogen atom or a C.sub.1 to C.sub.3 alkyl group, and in which between about 0.5 and 5 mol % of Z are radicals of aromatic dihydroxyketones. These polycarbonates share mechanical and thermal properties with known polycarbonates but in addition are suitable for crosslinking, for example in the presence of photoinitiators and optionally photo-reducing agents and under irradiation with UV light. When crosslinked they are resistant to organic solvents and insensitive to stress-cracking, and have particularly good flame-repellent properties when additionally incorporating flameproofing agents.
摘要:
The present invention relates to a process for the preparation of carbonic acid esters of polyester-polyols by transesterifying the polyols with carbonic acid aryl esters at elevated temperatures under vacuum in the presence of a catalyst. The reaction conditions are controlled to avoid the formation of by-products and the chain extension of the polyester-polyols. The present invention is also concerned with the polyester carbonic acid esters so formed, their use in producing polycarbonate block copolymers and the copolymers so produced. The copolymers may be produced by transesterifying the polyester carbonic acid esters with bisphenols and subjecting the bis-hydroxyaryl carbonates so formed to normal polycarbonate synthesis such as interfacial or melt polycondensation.
摘要:
The present invention relates to polycondensates of the formula 10, their use for absorbing metal ions of the transition elements of the periodic system and their use for the preparation of polymers containing metals of formula 11 which have e.g. improved resistance to heat and to chemicals compared to the corresponding polycondensates of formula 10.
摘要:
The sensitivity of silver halide emulsions is increased if the silver halide is precipitated in the presence of a peptization agent which consists partially or wholly of a copolymer comprising 0.1 to 20 mol% of recurring structural units of the formula ##STR1## in which X is hydrogen or alkyl having 1 to 4 carbon atoms and Y is a 8-hydroxyquinoline group attached through its 5- or 7-position.
摘要:
Homo- and copolymers of monomers obtained by acylation of 2-[4-hydroxy(or amino)phenyl]-2-[5-(8-hydroxyquinolyl)]-propane with .alpha.,.beta.-monoolefinically unsaturated carboxylic acid halides or - anhydrides. As comonomers can be employed compounds containing one or more .alpha.,.beta.-olefinically unsaturated groups such as olefines, diolefines, acrylic acid derivatives, vinyl monomers. The polymers having molecular weights between 5000 - 500,000 can be prepared by radical or ionic chain mechanisms, in continuous or discontinuous processes. They may be used for removing metal ions from their solution, for complexing of interfering metallic impurities in thermoplastic or thermosetting resins or in form of their metal complexes as stabilizers for plastics.
摘要:
The invention relates to the use of amino terminated phosphonamides and their oligomers, as flame retardant additives for a variety of polymers to impart flame retardancy while maintaining or improving processing characteristics and other important properties.
摘要:
Disclosed are random copoly(phosphonate carbonate)s with the high molecular weight and narrow molecular weight distribution exhibiting a superior combination of properties compared to prior art.
摘要:
Disclosed is a new method and compositions from the method consisting of block copolycarbonate/phosphonates that exhibit an excellent combination of flame resistance, hydrolytic stability, high Tg, low melt viscosity, low color and high toughness. Also disclosed are polymer mixtures or blends comprised of these block copolycarbonate/phosphonate compositions and commodity and engineering plastics and articles produced therefrom. Further disclosed are articles of manufacture produced from these materials, such as fibers, films, coated substrates, moldings, foams, adhesives and fiber-reinforced articles, or any combination thereof.
摘要:
Disclosed are new compositions consisting of polyphosphonates and specific additive compositions that exhibit superior resistance to degradation due to exposure to air, high temperature and air, moisture or combinations thereof. Also disclosed are polymer mixtures or blends comprising these polyphosphonates/additive compositions and commodity and engineering plastics and articles produced therefrom. Further disclosed are articles of manufacture produced from these materials, such as fibers, films, coated substrates, moldings, foams, fiber-reinforced articles, or any combination thereof.
摘要:
A method for preparing substantially pure optionally substituted diaryl alkylphosphonates from an optionally substituted triarylphosphite and an optionally substituted trialkylphosphite or an optionally substituted alkanol under special reaction conditions is described.