A non-formaldehyde liberating impregnant for bonding fibrous and granular substrates (e.g. glass fibre, textile fibres, wood chips etc), enabling the production of formed mouldings is described in this patent application. The composition essentially comprises an epoxy (and/or hydroxyalkyl) functional polymer dispersion formed in the presence of a low MW (3000 to 20000 g/mol) carboxyl-functional solution polymer (preferably polyAA). This solution polymer may be prepared in situ or a proprietary resin may be used. Emulsion copolymerisation of selected monomers is conducted in the presence of typically 40-60 wt% of the solution polymer, using a delayed pre-emulsified monomer addition procedure. The monomer system selected will depend on end application requirements with the primary monomers typified by comonomer compositions of (meth)acrylic esters, VA/ethylene and St/Bd systems.
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