摘要:
Polyethyleneterephthalate (PET) originating from the sorted collection of solid urban refuse can be regraded and recycled as such or mixed with virgin PET if treated at high temperature with an oxazoline of general formula: ##STR1##
摘要:
In the present invention, a class of catalysts is described, to be used in the polycondensation stage in the synthesis of poly(ethylene terephthalate), constituted by a composition of metal derivatives in quantity so that the content of these in the final polymer is below 130 ppm.
摘要:
Polyester compositions with a high crystallization rate obtained by mixing, at a high temperature, a polyester resin with at least one organic compound having the general formula:ROOC--Ar--OOC--Ar'--COO--Ar--COOR (I)where R represents a hydrogen atom or a C.sub.1 -C.sub.4 alkyl radical whereare Ar and Ar', either the same or different, represent a simple or condensed aromatic radical containing from 6 to 12 carbon atoms, and cooling the mixture thus obtained to room temperature.
摘要:
A mixed-matrix composite material reinforced with continuous fibre comprising a flexible sheath of thermoplastic polymer covering a multifibre filament impregnated with a powder consisting of:50-99% by weight, and preferably 70-95%, of a thermoplastic polymer;50-1% by weight, and preferably 30-5%, of a C.sub.2 -C.sub.4 olefin/carbon monoxide alternating polymer having an intrinsic viscosity exceeding 0.1 dl/g when measured in m-cresol at 100.degree. C.
摘要:
Polyesters with a high crystallization rate synthesized by the polycondensation of terephthalic acid with at least one C.sub.2 -C.sub.4 alkylenic glycol in the presence of 0.1-1.5 mol % of a copolymerizable reagent having the general formula:ROOC--Ar--OOC--Ar'--COO--Ar--COORwhere Ar and Ar'represent aromatic radicals and R represent a halogen, a hydrogen atom or a C.sub.1- C.sub.4 alkyl radical.
摘要:
Low-crystallization-speed polyesters obtained by means of the polycondensation of 2,6-naphthalene-dicarboxy acid with at least one (C.sub.2 -C.sub.10)-(cyclo)alkylene glycol in the presence of 0.5-50 mol % of a copolymerizable reactant of general formula:ROOC--Ar--OOC--Ar'--COO--Ar--COOR (I)wherein Ar and Ar' stand for aromatic radicals, and R stands for a hydrogen atom or a (C.sub.1 -C.sub.4)-alkyl radical, or the OR group is replaced by a halogen.
摘要:
Low-crystallization-speed polyesters obtained by means of the polycondensation of terephthalic acid with at least one (C.sub.2 -C.sub.10)-(Cyclo)alkylene glycol in the presence of 2-50 mol % of a copolymerizable reactant of general formula:ROOC-Ar-OOC-Ar'-COO-Ar-COOR (I)wherein Ar and Ar' stand for aromatic radicals, and R stands for a hydrogen atom or a (C.sub.1 -C.sub.4)-alkyl radical, or the OR group is replaced by a halogen.
摘要:
A parison for transparent re-usable bottles, obtained by molding by injection-blow moulding cycle copolymers containing units deriving from terephthalic acid and ethylene glycol characterized in that said copolymers contain from 0.1 to 10% in moles of units deriving from aromatic diacids different from terephthalic acid and from 0.1-15% in moles of units deriving from aromatic hydroxyacids, making reference to the units deriving from terephthalic acid.
摘要:
Copolyesters having an improved combination of barrier, mechanical, thermal and rheological properties and consisting of acylic and glycolic radicals, wherein the acylic radicals derive from at least isophthalic acid and 2,6-naphthalene dicarboxylic acid and at least 90% by mols of the glycolic radicals derive from ethylene glycol.
摘要:
Process for the preparation of transparent re-usable bottles, which consists in moulding by injection-blow moulding cycle copolymers containing units deriving from terephthalic acid and ethylene glycol characterized in that said copolymers contain from 0.1 to 10% in moles of units deriving from aromatic diacids different from terephthalic acid and from 0.1-15% in moles of units deriving from aromatic hydroxyacids, making reference to the units deriving from terephthalic acid.