A device for diffusing an active substance such as a odorant or insecticide into the atmosphere at a substantially uniform rate. The device comprises a block impregnated with the substance. The block consists of a plurality of slabs, for example, of a gelatine or cellulose derivative, suitably held together.

Insecticide evaporator comprising at least one volatile phosphoric ester insecticide, an agent for stabilizing the said ester against decomposition by protonization and used in an amount of 0.2 to 20% based on the weight of phosphoric ester, characterized in that the stabilizing agent contains at least one compound selected from the compounds of the chemical class of 1,3-benzodioxoles and at least one diazene.

Insecticide evaporator comprising at least one volatile phosphoric ester insecticide, an agent for stabilising the said ester against decomposition by protonisation and used in an amount of 0.2 to 10 % based on the weight of phosphoric ester, characterised in that the stabilising agent contains at least one compound selected from the compounds of the chemical class of 1,3-benzodioxoles and the balance of said stabilising agent being selected from elemental sulphur, a compound of divalent sulphur, a diazene and an epoxidized compound.

The instant invention relates to a method for converting phosphorus containing polymers from a two dimensional, layered structure into a three dimensional structure by crosslinking such layers. The method and the resulting crosslinked polymers may be used to encapsulate active materials such as catalysts, pesticides, etc. by intercalating such active materials between the layers prior to crosslinking. Thus, the egress of said active materials into the environment during use may be hindered or prevented. The crosslinking polymers, themselves, may also be used as catalysts or as selective sorbents.

A chemical complex of a biocidal agent such as ortho-phenylphenol and chlorpyrifos and a non-ionic polymer of 2-ethyl oxazoline (PEOx). The complex is compatible with and contained in a plastic film such as polyethylene, polypropylene and poly(vinyl chloride) and the product is characterized by a reduced rate of release of the biocide without adversely affecting either the properties of the biocide or the film itself. The biocide-impregnated plastic finds utility in bags and in packing used to inhibit fungicidal growth and to prevent attack by insects and bacteria during growing, drying, packing, shipping, storage and marketing of fruits and vegetables.