摘要:
Aromatic polyesters based on diphenols, terephthalic and isophthalic acid and particular chain terminators exhibit an improved color number, an improved flowability and increased dimensional heat stability with otherwise comparable mechanical characteristics.
摘要:
A process for preparing a polyarylene sulphide which comprises reacting(a) dihalogenobenzene consisting of 50 to 100 mol % of a compound of the formula ##STR1## or a compound of the formula ##STR2## or a mixture thereof and of 0 to 50 mol % of a compound of the formula ##STR3## wherein X is halogen and each R is selected from the group consisting of hydrogen, alkyl having 1 to 20 carbon atoms, cycloalkyl having 5 to 20 carbon atoms, aryl having 6 to 24 carbon atoms, alkaryl having 7 to 24 carbon atoms and aralkyl having 7 to 24 carbon atoms with the proviso that at least one R is other than hydrogen and(b) 0 to 3.0 mol % based on the dihalogenobenzene content of a polyhalogeno aromatic of the formulaArX.sub.n (IV) wherein Ar is an aromatic or heterocyclic radical with 6 to 24 carbon atoms having at least 3 free valencies, X is halogen and n is .gtoreq. 3 with(c) an alkyl metal sulphide in(d) a polar solvent in the presence of(e) 0.05-2.0 mol of alkali metal fluoride per mol of alkali metal sulphide,for a polycondensation time of up to 30 hours and at a polycondensation temperature of between 160.degree. and 295.degree. C., the molar ratio of (a) to (c) being in the range from 0.85:1 to 1.15:1 and the molar ratio of (c) to (d) being in the range of from 1:2 to 1:15.
摘要:
The invention relates to a process for the preparation of optionally branched, high molecular weight polyarylene sulphides with melt viscosities which can be established at defined values and low corrosion.These polyarylene sulphides are obtained by reacting alkali metal sulphides, if appropriate mixed with alkali metal bisulphides and reaction accelerators, with dihalogenoaromatics and, if appropriate, polyhalogenoaromatics, with the addition of particular monohalogenoaromatics as chain stoppers.
摘要:
High molecular weight p-polyarylensulfides having a high melt viscosity, capable of being processed thermoplastically, and have good mechanical properties are produced by reacting components (a), (b), and (c) in a polar solvent with a molar ratio of (a):(c) in the range of 0.85:1 to 1.15:1 and a molar ratio of (c): solvent in the range of 1:2 to 1:15, for a time of up to 10 hours at a temperature of from 160.degree. C. to 300.degree. C., and in the presence of from 2 to 100 mole percent, relative to (c), of an N,N-dialkylcarboxamide;wherein component (a) is dihalogenobenzene with 50 to 100 mole percent of the formula ##STR1## and 0 to 50 mole percent of the formula ##STR2## wherein X is fluoro, chloro, bromo or iodo, and R is the same or different and each is selected from the group consisting of hydrogen, alkyl having 1 to 20 carbon atoms, cycloalkyl having 5 to 20 carbon atoms, aryl having 6 to 24 carbon atoms, alkaryl having 7 to 24 carbon atoms, aralkyl having 7 to 24 carbon atoms, and two R moieties linked together forming aryl having 6 to 24 carbon atoms or a heterocyclic moiety having an oxygen, nitrogen or sulphur hetero-atom and having 6 to 24 carbon atoms; with the proviso that at least one R is not hydrogen;component (b) is 0.1 to 2.4 mole percent, relative to the dihalogenobenzene, of a polyhalogenoaromatic of the formulaArX.sub.nwherein Ar is aryl or a heterocyclic moiety having an oxygen, nitrogen or sulphur heteroatom with said aryl and said heterocyclic each having from 6 to 24 carbon atoms;X is fluoro, chloro, bromo or iodo; andn is 3 or 4;and component (c) is alkali metal sulphide.
摘要:
Process for preparing polyarylensulfides by reacting dihalogenobenzenes, optionally substituted with polyhalogenoaromatic compounds with 3 or 4 halogeno substituents, and alkali metal sulfide in polar solvents using alkali metal sulfites and/or alkaline earth metal sulfites as catalysts.
摘要:
The invention relates to a process for the preparation of high-molecular, optionally branched polyarylene sulphides. These can be prepared without a catalyst in a polar organic solvent by reacting dihalogenoaromatic compounds with mixtures of sodium and potassium sulphides and hydrogensulphides.
摘要:
The invention relates to an anhydrous process for the preparation of high molecular weight, optionally branched polyarylene sulphides. These can be prepared in a polar organic solvent in the absence of water by reaction of dihalogenoaromatics with sodium sulphides and bisulphide or potassium sulphides and bisulphide in the presence of catalysts in a polar organic solvent.
摘要:
The invention relates to a process for the preparation of polyarylene sulphides in alkylated polyureas at a temperature of 250.degree. to 290.degree. C. under a pressure from 4 to 50 bars.
摘要:
The invention relates to a process for the production of optionally branched polyarylene sulfides by reacting dihalogen benzenes in admixture with aromatic polyhalogen compounds and alkali sulfides in polar solvents, the reaction being carried out in the presence of reducing agents.