Fire retardant particulate expandable styrene polymers
Abstract
Abstract Fine particulate expandable flame retardant styrene polymers having an improved minimum mold dwell time and reduced block shrinkage are prepared by: (a) mixing together styrene monomer or a mixture of styrene and a copolymerizable monomer with an organic halogen compound and an expanding agent in an aqueous dispersion; (b) adding before or during polymerization to the mixture of (a) from 0.0001 to 0.1% by weight of an expoxidation product of an aliphatic hydrocarbon of which the epoxidated aliphatic chain comprises from 6 to 18 C atoms, this epoxidation product being soluble in the monomers; (c) carrying out a polymerization in the aqueous suspension of (a) and (b) using radical forming initiators at temperatures of 80 DEG C.-130 DEG C. to form expandable particles; (d) pre-forming the expandable particles resulting from (c); ageing the pre-formed particles of (d); and (f) molding the pre-formed and aged particles of (e) in a pressure resistant mold.
Inventors
- 👤 Josef K. Rigler
- 👤 Ekkehard Wienhofer
- 👤 Horst Leithauser
- 👤 Karl Trukenbrod
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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