Flameproofing plastics with synergistic fire retardants - by microencapsulating fire retardants, e.g. antimony tri:oxide and organic bromo cpd., in material which is compatible with the host plastic

摘要

Flameproofing plastics with synergistic fire retardants (I) based on metal cpds. (e.g. Sb2O, Zn borate) and brominated organic cpds. comprises microencapsulating (I) with a material (II) which is compatible with the host plastic and then adding it to the plastic. Pref. (II) are thermoplastic, thermosetting or elastic organic materials. The microcapsules have dia. of 1-100 mm and are free-flowing, with wt. ratio (II):(I) of (3:1)-(1:3). Concn. of microcapsules in the plastic is 0.1-20 wt.%. (I) can be processed as an application-oriented masterbatch. Microencapsulation is carried out, e.g. by spray drying, polymerisation from monomer solns., complex coacervation between positive and negative colloid polymers, etc. USE/ADVANTAGE - The process is applicable to all known synergistic fire retardant systems; it enables improved incorporation of (I) into the host material, without adversely affecting mechanical/physical or processing properties; in case of fire, only sufficient (I) to extinguish the flame is exposed, and the process is therefore environmentally friendly; migration of (I) does not occu