Abstract: An article intended to be degraded when exposed to the environment is made from a brittle resinous or synthetic resin material incorporating moisture swellable particles as a filler, whereby exposure of the article to water induces fragmentation. In particular, hydrodegradable "clay pigeons" for shot-gun shooting may be made from a mixture of pitch, powdered limestone or chalk and dry potato starch. Exposure of such a "clay pigeon" or fragments thereof, to water causes swelling of the starch particles and consequent fragmentation of material into, eventually, a fine sludge which is ultimately absorbed into the ground.

Abstract: A degradable polymer composition is disclosed which comprises a blend of a normally stable chemically saturated polymer, such as polyethylene, a less stable chemically unsaturated polymer or copolymer, such as a styrene/butadiene block copolymer, or natural rubber, an antioxidant active over a limited period and a latent pro-oxidant, such as an organic salt of a transition metal, e.g. cobalt naphthenate. The presence together of the anti-oxidant and the pro-oxidant give rise to a period of induction before a sharp loss of physical strength occurs, whereby the period of induction can be exploited as the effective working life of the polymer composition.

Abstract: A degradable polymer composition is disclosed which comprises a blend of a normally stable chemically saturated polymer, such as polyethylene, a less stable chemically unsaturated polymer or copolymer, such as a styrene/butadiene block copolymer, or natural rubber, an antioxidant active over a limited period and a latent pro-oxidant, such as an organic salt of a transition metal, e.g. cobalt naphthenate. The presence together of the anti-oxidant and the pro-oxidant give rise to a period of induction before a sharp loss of physical strength occurs, whereby the period of induction can be exploited as the effective working life of the polymer composition.

Abstract: A plastics-based composition comprising a polyester resin and starch granules which, prior to mixing with the resin, are rendered reactive with the resin by a surface implant of alkali metal or alkaline earth metal ions.

Abstract: A board or similar product is made from fibrous spent hops, the resin content of which sets the product. The product is preferably formed by catalyzed hot-pressing.

Abstract: In the manufacture of products made of starch filled plastics the polymer and starch granules are mixed with a lubricant immediately prior to forming. A feedstock material in accordance with the invention comprises paticles of starch granules in admixture with a lubricant such as an oil or wax.

Abstract: A device for oral administration to a ruminant animal includes a veterinary medicament, such as an anthelmintic, uniformly dispersed throughout an erodable sheet comprising an ethylene-vinylacetate copolymer. The sheet is rolled up and stuck together with adhesive backed paper strips for administration, and unrolls in the rumen to take up a planar configuration which is retained in the rumen. The sheet may be placed within a plastics netting envelope to give more controlled erosion and release of medicament.

Abstract: A device for oral administration to a ruminant animal includes a veterinary medicament, such as an anthelmintic, uniformly dispersed throughout an erodable sheet comprising an ethylene-vinylacetate copolymer. The sheet is rolled up and stuck together with adhesive backed paper strips for administration, and unrolls in the rumen to take up a planar configuration which is retained in the rumen. The sheet may be placed within a plastics netting envelope to give more controlled erosion and release of medicament.

Abstract: Sustained release composition comprising a water soluble veterinary medicament dispersed in a sheet of water insoluble polymer, which sheet is of a size and composition such that it is capable of being constrained in a position which allows oral administration and is, in the rumen, capable of moving relative to this position to retain the composition therein.

Abstract: In the manufacture of products made of starch filled plastics the polymer and starch granules are mixed with a lubricant immediately prior to forming. A feedstock material in accordance with the invention comprises particles of starch granules in admixture with a lubricant such as an oil or wax.

Abstract: A biodegradable composition contains a high proportion, i.e., over 50% of biodegradable starch. The composition is particularly useful for making trays for holding meat. These trays are liquid repellant but gas permeable.