Polymeric materials and additives therefor
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.
1. A container or a preform for a container, wherein said container or preform comprises a composition which comprises a polymeric material and an inorganic material selected from indium tin oxide, reduced indium tin oxide and antimony tin oxide.
2. A container or preform as claimed in claim 1 , which includes at least 0.01 ppm and less than 1000 ppm of said inorganic material based on the weight of said polymeric material.
3. A container or preform as claimed in claim 1 , wherein at least 90% of said inorganic material comprises particles having a maximum dimension which is less than 10 microns.
4. A container or preform as claimed in claim 1 , wherein the inorganic material is colloidal or nanoparticulate matter.
5. A container or preform as claimed in claim 1 , wherein the polymeric material is selected from one or more of the following polymers: polyesters, polycarbonates, polyamides, polyolefins, polystyrenes, vinyl polymers, acrylic polymers and copolymers and blends thereof.
6. A container or preform as claimed in claim 1 , wherein said polymeric material comprises poly(ethylene terephthalate).
7. A container or preform as claimed in claim 1 , wherein said container is stretch blow moulded.
8. A method of making a container, the method comprising:
(a) selecting a preform for a container wherein said preform comprises a composition which comprises a polymeric material and an inorganic material selected from indium tin oxide, reduced indium tin oxide and antimony tin oxide; and
(b) heating the selected preform and forming it into a container.
9. A method as claimed in claim 8 , wherein, in said method, the composition is heated using an infrared source.
10. A method of improving the reheat characteristics of a polymeric material, the method comprising contacting the polymeric material or contacting one or more monomers or oligomers or prepolymers arranged to be polymerised to prepare the polymeric material with an inorganic material selected from indium tin oxide, reduced indium tin oxide and antimony tin oxide, wherein said inorganic material is dispersed in the polymeric material and said polymeric material includes at least 0.01 ppm and less than 1,000 ppm of said inorganic material based on the weight of said polymeric material.
11. A method according to claim 10 , wherein granules or pellets which comprise the polymeric material and inorganic material are prepared.
12. A method according to claim 10 , wherein said polymeric material comprises poly(ethylene terephthalate).
13. A method according to claim 10 , wherein at least 90% of said inorganic material comprises particles having a maximum dimension which is less than 10 microns.
14. A composition with improved reheat characteristics, said composition comprising a polymeric material and an inorganic material dispersed in the polymeric material, wherein said composition includes at least 0.01 ppm and less than 1,000 ppm of said inorganic material based on the weight of said polymeric material; and wherein said inorganic material is selected from indium tin oxide, reduced indium tin oxide and antimony tin oxide.
15. A composition according to claim 14 , wherein said polymeric material comprises poly(ethylene terephthalate).
16. A composition according to claim 14 , wherein the inorganic material is colloidal or nanoparticulate matter.
17. A method of improving the reheat characteristics of a polymeric material, the method comprising contacting the polymeric material or contacting one or more monomers or oligomers or prepolymers arranged to be polymerised to prepare the polymeric material with an inorganic material selected from indium tin oxide, reduced indium tin oxide and antimony tin oxide, wherein granules or pellets which comprise the polymeric material and inorganic material are prepared.