Abstract: Thermoplastic polymers, for example fluoropolymers, are foamed by use of a solid formulation comprising thermoplastic polymer and manganese oxalate.

Abstract: High pressure injection apparatus (2) for addition of a liquid formulation into a melt stream comprises a first pump which is arranged to accurately meter the liquid formulation (including highly loaded formulations comprising solids comprising particles of relatively large size) and a second pump which boosts the pressure of the formulation to that of the melt stream into which it is to be injected. In an embodiment, the apparatus includes a tank (4) for initially receiving liquid formulation. The tank is subjected to ambient temperature and pressure and need not be stirred or otherwise agitated. The tank is arranged to deliver the formulation via pipe (6) into a first pump (8) (which may be a diaphragm pump or a progressing cavity pump). The pump is arranged to work at a pressure up to 120 bar to boost pressure. Downstream of pump (8), a pipe (10) is arranged to deliver formulation from the pump (8) to a gear pump (12), driven by a motor (13). The gear pump acts to meter the liquid formulation.

Abstract: The present invention relates to the use of a fatty acid ester as a slip additive in the production of molded polyethylene terephthalate articles, to a thermoplastic molding composition comprising a polyethylene terephthalate and a fatty acid ester selected to be effective for reducing the co-efficient of friction of molded articles formed from the composition, to a molded polyethylene terephthalate article comprising a fatty acid ester selected to be effective in reducing the co-efficient of friction of the molded article, and to a process for producing a molded thermoplastic article comprising providing a thermoplastic molding composition comprising polyethylene terephthalate, admixing with the thermoplastic molding composition at least one fatty acid ester selected to be effective in reducing the co-efficient of friction of the molded article, heating the composition and molding the hot composition so as to form a molded article.

Abstract: A polymer additive for improving the reheat characteristics of a polymer or polymeric composition comprises an inorganic material which is such that a 2.5 mm thick polyethylene terephthalate plaque incorporating the inorganic material has, when tested, an absorption ratio of less than 0.9, wherein the absorption ratio is either the ratio of A1/A2 or the ratio A1/A3, wherein: A1 is the maximum absorption between 400 nm and 550 nm; A2 is the maximum absorption between 700 to 1100 nm; A3 is the maximum absorption between 700 to 1600 nm. Preferred inorganic materials are titanium nitride, indium tin oxide and lanthanum hexaboride.

Abstract: A process for recycling a coloured thermoplastic material comprising an absorbed disperse dye comprises contacting the optionally comminuted coloured thermoplastic material with a caustic wash and recovering an at least partly colour-modified thermoplastic composition from the caustic wash.

Abstract: A polymer additive for improving the reheat characteristics of a polymer or polymeric composition comprises an inorganic material which is such that a 2.5 mm thick polyethylene terephthalate plaque incorporating the inorganic material has, when tested, an absorption ratio of less than 0.9, wherein the absorption ratio is either the ratio of A1/A2 or the ratio A1/A3, wherein: A1 is the maximum absorption between 400 nm and 550 nm; A2 is the maximum absorption between 700 to 1100 nm; A3 is the maximum absorption between 700 to 1600 nm. Preferred inorganic materials are titanium nitride, indium tin oxide and lanthanum hexaboride.

Abstract: This invention relates to moulded polyethylene terephthalate articles and to a process for making them.

Abstract: A polymer additive for improving the reheat characteristics of a polymer or polymeric composition comprises an inorganic material which is such that a 2.5 mm thick polyethylene terephthalate plaque incorporating the inorganic material has, when tested, an absorption ratio of less than 0.9, wherein the absorption ratio is either the ratio of A1/A2 or the ratio A1/A3, wherein: A1 is the maximum absorption between 400 nm and 550 nm; A2 is the maximum absorption between 700 to 1100 nm; A3 is the maximum absorption between 700 to 1600 nm. Preferred inorganic materials are titanium nitride, indium tin oxide and lanthanum hexaboride.

Abstract: Use of a hindered amine light stabiliser as an additive in a thermoplastic moulding composition comprising polyethylene terephthalate and an acetaldehyde scavenger for reducing the degree of discolouration and/or degree of light transmission of a moulded article formed from the composition.

Abstract: A polymer additive for improving the reheat characteristics of a polymer or polymeric composition comprises an inorganic material which is such that a 2.5 mm thick polyethylene terephthalate plaque incorporating the inorganic material has, when tested, an absorption ratio of less than 0.9, wherein the absorption ratio is either the ratio of A1/A2 or the ratio A1/A3, wherein: A1 is the maximum absorption between 400 nm and 550 nm; A2 is the maximum absorption between 700 to 1100 nm; A3 is the maximum absorption between 700 to 1600 nm. Preferred inorganic materials are titanium nitride, indium tin oxide and lanthanum hexaboride.