摘要:
A three-step process for the production of solventless polycarbonate is disclosed. Accordingly, a mixture of two different oligocarbonates each prepared by the interfacial method, is prepared in the first process step. In a second step, the mixture is crystallized. The third step entails polycondensation. In an additional embodiment of the invention the first step uses a mixture of one oligocarbonate with a suitable monomer.
摘要:
Aromatic polyesters are prepared by the transesterification of aromatic dicarboxylic acid dialkyl esters with diester derivatives of divalent phenols at temperatures of about 260.degree. to 350.degree. C. with removal of the resulting monocarboxylic acid alkyl ester from the reaction mixture.
摘要:
The invention relates to ternary thermoplastic mixtures of polycarbonates, polyurethanes and graft polymers and, optionally, standard additives and to processes for the production of these mixtures.
摘要:
Fire-retardant polycarbonates, polyester carbonates and polyesters based on dihydroxydiphenyl cycloalkanes ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent hydrogen, halogen, preferably chlorine or bromine, C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl, preferably phenyl and C.sub.7 -C.sub.12 aralkyl, preferably phenyl-C.sub.1 -C.sub.4 -alkyl, more especially benzyl,m is an integer of 4 to 7, preferably 4 or 5, R.sup.3 and R.sup.4 may be individually selected for each X and, independently of one another, represent hydrogen or C.sub.1 -C.sub.6 alkyl andX is carbon,with the proviso that, at at least one atom X, R.sup.3 and R.sup.4 are both alkyl,the fire-retardant finish being provided by additives and/or comonomers.
摘要:
Aromatic polyesters based on diphenols and iso- and/or terephthalic acid are produced by transesterification of esters of the diphenols with the aromatic dicarboxylic acids in the melt by first reacting the aromatic dicarboxylic acids with a stoichiometric excess of the diphenol esters to form oligomers and then condensing the resulting oligomers to the aromatic polyesters with elimination and removal by distillation of diphenol ester.
摘要:
This invention relates to mixtures of thermoplastic aromatic poly(ester)carbonates with thermoplastic polyurethanes containing special graft polymers and, optionally, suitable additives, to a process for their production and to the use of the mixtures according to the invention for the production of moldings, particularly by injection molding or extrusion.
摘要:
This invention relates to the use of polyphenylene oxides corresponding to the following general formula: ##STR1## for the production of aromatic block polyether-poly(ester) carbonates by the interfacial process and also to the block polyether-poly(ester) carbonates obtainable by the process.
摘要:
The invention relates to a process for the preparation of aromatic polyester-carbonates wherein, in a first stage, aromatic oligo-esters or oligo-ester-carbonates having hydroxyl end groups are prepared from diaryl esters of aromatic dicarboxylic acids (or their starting materials) and diphenols and, optionally, a diaryl carbonate, by trans-esterification in the melt, and in a second stage these oligo-esters or oligo-ester-carbonates are condensed with phosgene by the phase boundary process to give the polyester-carbonate.
摘要:
The present invention provides moulding compositions consisting of polyphenylene oxide/polycarbonate block condensates, graft polymers and, where appropriate, co-polymers. These moulding compositions can contain further suitable additives. The present invention also provides a process for preparing the moulding compositions according to the invention.
摘要:
Small quantities of hydrogenated polybenzyls act as a perfect mould release agent for aromatic polyesters based on diphenols and iso- and/or terephthalic acids and do not appreciably impair the elastic strength characteristics, the dimensional stability under heat and the transparency.