Abstract:
A method of decreasing aldehyde content in polymeric materials, for example in bottles comprising polyethylene terephthalate, uses a compound (A) which comprises first, second and third fragments which comprise a moiety Fomula A) (A) and a moiety. (Formula B) NH (B).
Abstract:
A formulation for foaming a thermoplastic polymer, for example PVC, comprises a carrier, exothermic and endothermic chemical blowing agents and 1 wt%, preferably less than 0.2 wt% of water. The liquid formulation can readily be used for foaming PVC and other thermoplastics.
Abstract:
A liquid formulation for dosing into a polymeric material, for example a polyolefin, in film or sheet production, comprises a solvent and a hindered amine light stabiliser dissolved in the solvent, wherein the sum of the wt% of all hindered amine light stabilisers in the formulation is at least 30 wt%.
Abstract:
A method of introducing an additive into a polymeric material comprises using a liquid formulation comprising an additive, for example a colourant, and a vehicle comprising an aliphatic or aromatic tri- or di-carboxylic acid covalently linked by ester bonds to two or more chains. The method involves contacting the liquid formulation with the polymeric material in a melt processing apparatus. The cavity transfer mixer may be used in the process. A fibre is suitably subsequently produced.
Abstract:
A liquid formulation for addition to a polymeric material comprises a vehicle, an additive (e.g. a colourant) and carbonyl bis (1 -caprolactan)). The liquid formulation may be used to colour melt spun fibre (e.g. PET or polyamide).
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. In an alternative embodiment, apparatus may include a progressing cavity pump to meter formulation and a gear pump to increase pressure. The apparatus may be used to inject a fluid formulation into a melted polymeric material.
Abstract:
A method of introducing an additive, for example a dye, into a polymeric material comprises using a liquid formulation comprising the additive, a vehicle and an active compound added to increase the melt viscosity of the polymeric material. The active compound may be a multi-functional anhydride. The liquid formulation is suitably contacted with the polymeric material in a melt processing apparatus and suitably a cavity transfer mixer is used in the process. A fibre is suitably subsequently produced.
Abstract:
Polymeric Materials An injector (14) for injecting liquid formulation into molten polymer includes a conduit (117) having regions (44, 46) which are secured within a wall of an extruder (19). Conduit (117) includes an annular collar (120) having an upwardly facing annular surface (122) which is arranged to bear against part of a sleeve nut (124). Conduit (117) is arranged within a port (125) which includes a screw-threaded wall (126). The sleeve nut (124) includes a cylindrical body (146) having an inwardly facing cylindrical wall which is arranged to define a cylindrical air gap (148) between itself and an outer wall (147) of conduit (117). Region (150) of the sleeve nut is screw-threadedly engaged in wall (126) of the extruder. In use, cool compressed air is introduced into the assembly in the direction of arrow (170) and it flows through the assembly to cool it.
Abstract:
A method of producing a product, for example a stretch blow moulded container having a metallic or pearlescent appearance, comprises selecting a mass, for example a container preform, comprising a thermoplastic polymer which incorporates a carrier polymer and stretching the thermoplastic polymer during production of said product, for example from said mass. Said carrier polymer is suitably polydimethylsiloxane and the mass may be made in a process which comprises contacting a thermoplastic polymer with a liquid formulation comprising carrier polymer and colourant.
Abstract:
Additives such as colourants may be incorporated into polymeric materials such as polyesters, such as in polyester fibre production, by use of a liquid formulation comprising colourant and a vehicle. The vehicle may comprise a functionalised pentaerythritol, trimethylolpropane or trimellitate. The liquid formulation is suitably contacted with the polymeric material in a melt processing apparatus.