Improvements of natural rubber for flame resistance

Songklanakarin Journal of Science and Technology 01/2010;
Source: DOAJ

ABSTRACT The present invention provides a process for treating natural rubber to increase its flame retardant capability. Theprocess comprises a mixture of a natural rubber with, (a) halogenated free flame retardant agent (zinc hydroxystannate;STORFLAM ZHS) and (b) halogenated flame retardant agent (decabromodiphenyl; Great Lake DE-83R and chlorinatedparaffins; Plastoil 152) and another material like antimony trioxide and aluminium hydroxide in appropriate amount, with ratio of halogenated flame retardant agent: antimony trioxide 3:1. In the resulting product with halogen flame retardant showed a more efficient flame retardant property than halogen free flame retardant, i.e. brominated flame retardant provide higher efficiency than chlorinated and ZHS, respectively. The minimum requirement ratio for being flame retardant of antimonytrioxide: brominated or chlorinated agent is 7:21 or 10:30 phr while aluminium hydroxide: ZHS is 10: 150 phr. It was found thatburning rate was zero for brominated and chlorinated agent used but not for zinc hydroxyl stannate system. Average time of burning (ATB) was 135, 118 and 41 second for brominated, chlorinated and ZHS flame retardant, respectively. Average extent of burning (AEB) was 24, 19 and 14 millimeters, respectively. An advantage of this invention is that chemicals (antimony trioxide and either brominated or chlorinated agent) added to natural rubber have the effect of rendering the natural rubber flame-resistant like synthetic rubbers, chloroprene.

Download full-text


Available from: Orasa Tim Patarapaiboolchai, Jul 28, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: The use of phosphorus for improving flame retardancy of natural rubber vulcanizates was attempted by incorporating a modified form of natural rubber. By reacting epoxidized liquid natural rubber (ELNR) with dibutylphosphate it was possible to chemically modify the polymer. On a 25% epoxidized LNR, 5.2–6.8% w/w of phosphorus could be fixed on the polymer backbone. The reaction carried out in bulk and solution resulted in products with different Tg values probably due to the varying crosslink levels in the resultant products. Chemical analysis of the modified polymers prepared by two sets of reactions under identical conditions proved the reproducibility of the reactions in bulk and in solution. Incorporation of the phosphorus-modified ELNR in a natural rubber formulation decreased the flammability behaviors of the vulcanizate. On the other hand, a decrease of the rate of curing and mechanical properties was observed. The phosphorus addition could also be carried out by mixing ELNR and dibutylphosphate at the time of mixing the compounds and resulted in equally good flame retardance with relatively better processing and mechanical properties. © 1994 John Wiley & Sons, Inc.
    Journal of Applied Polymer Science 01/1994; 52(9):1309 - 1316. DOI:10.1002/app.1994.070520915 · 1.64 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The thermal degradation of a phosphate methacrylate polymer was monitored by in-situ FTIR, XPS, XRD and Raman measurements to investigate the variation in chemical structure and element contents, as well as the carbon structure of the final char formed after burning. The results show that the phosphate group decomposes easily in the range 200–250 °C. The degraded products further react with aromatic polynuclear hydrocarbons, formed above 270 °C to give phosphorus-carbon complexes. These complexes finally condense to form a graphite-like structure with an interplanar distance of 3.62Å.
    Polymer Degradation and Stability 05/2003; 80(2-80):217-222. DOI:10.1016/S0141-3910(02)00401-9 · 2.63 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The use of synthetic polymeric materials in numerous consumer-oriented applications has increased rapidly over the past few decades. This trend has caused considerable concern regarding the responses of these materials to fire, and this concern has resulted in a flurry of activities by numerous agencies (private government) directed toward better characterization of the flammability of manmade polymers as well as toward regulations to reduce any potential hazard these materials may present. This bibliography based review paper is concluded with flammability, toxicity of synthetic rubbers. The discussion is presented under headings - introduction; pyrolysis and flame retardation; smoke and toxicity; flammability testing; applications. The review covers the following elastomers - polychloroprene, chlorosulfonated PE, chlorinated PE, fluorocarbons, polyurethanes, epichlorohydrin polymers, silicons, nitroso and triazine elastomers, polyphosphazenes, and miscellaneous elastomers.
    Rubber Chemistry and Technology 07/1977; 50(3):523-569. DOI:10.5254/1.3535157 · 1.20 Impact Factor