Thermoplastics formulation

Bourbigot, S., Le Bras, M., Tremillon, J.-M., Breant, P., and Delobel, R. 1996. Zeolites New synergistic agents for intumescent thermoplastic formulations—Criteria for the choice of the zeolite. Fire Mater. 20 145-158. 

The demands on a flame retardant and thermoplastics formulated with such agents are manifold. The flame retardant should provide a durable flame-retarding effect by the addition of only small quantities of the additive it should be as cheap as possible and the manner of incorporation should be easy it should be nontoxic and should not produce fire effluents with increased toxicity it should not decompose at the processing temperatures it should not volatilize and smell and the mechanical, optical, and physical properties of the thermoplastics should be affected as little as possible. It is understandable that these far-ranging demands cannot be satisfied by only one flame retardant and for all thermoplastics with their manifold applications. One is therefore forced to seek the optimum flame retarding formulation for each thermoplastic and the specific application. Examples of typical formulations of several flame-retarded thermoplastics are given in Appendix A8. 

Though the overall impact result of the hemp/epoxy composite was lower than the impact of the glass/epoxy composite, the impact associated with the matrix was very high. There are two ways to reduce the impacts associated with the matrix one is using bio-based matrix, the other is using a recycled matrix. Many studies involve the use of bio-based epoxy resin in thermoset composites, while recycled polypropylene and recycled polyethylene have been studied in new thermoplastic formulations. 

APP and APP-based systems are very effident halogen-free flame retardants mainly used in polyolefins (PE, PP), epoxies, polyurethanes, unsaturated polyesters, phenolic resins, and others. APP is a nontoxic, environment friendly material and it does not generate additional quantities of smoke due to intumescence. Compared to other halogen-free systems, APP requires lower loadings. In thermoplastic formulations, APP exhibits good processability, retention of good mechanical properties. 

Although most SMC formulations are based on traditional polyester and random fibre mat, there are many variants available today some are based on vinyl ester, and others include a small proportion of thermoplastics. Formulations designed for high rigidity applieations like bumper beams may contain around 60% of glass fibres, most of them uni-directional. 

Le Bras, M. Bourbigot, S. Felix, E. Pouille, F. Siat, C. Traisnel, M. Characterization of polyamide-6-based intumescent additive for thermoplastic formulations. Polymer 2000, 41(14), 5283-5298. 

Flame Retardant for thermoset and thermoplastic formulations, intumescent systems... 

The hydrogel materials in the dry state (xerogels) show UTS and UCS ranging from 13 to 34 MPa and from 39 to 98 MPa, respectively, and tensile and compression moduli ranging from 0.9 to 3 GPa and from 0.15 to 1.9 GPa, respectively ". There is a tendency for an increase of all mechanical properties with the increase of AAm content in the thermoplastic formulations, but no clear correlations are found with the solid/liquid ratio. The crosslinked materials show improved mechanical properties when compared with the thermoplastics, especially for higher crosslinking densities and higher SEVA-C contents. ... 

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