Alumina trihydrate high loadings

TrialkylPhosphates. Triethyl phosphate [78-40-0] C H O P, is a colorless Hquid boiling at 209—218°C containing 17 wt % phosphoms. It may be manufactured from diethyl ether and phosphoms pentoxide via a metaphosphate intermediate (63,64). Triethyl phosphate has been used commercially as an additive for polyester laminates and in ceHulosics. In polyester resins, it functions as a viscosity depressant as weH as a flame retardant. The viscosity depressant effect of triethyl phosphate in polyester resins permits high loadings of alumina trihydrate, a fire-retardant smoke-suppressant filler (65,66). 

As a result, several inorganic compounds have found application in this field, and alumina trihydrate, A1(0H)-, is now by far the highest volume flame retardant (3). Its use, however, is limited to those polymers which can tolerate the exceptionally high loadings required to be effective, without seriously affecting the mechanical properties of the substrate (7 ). 

Features Med. soft hand exc. str. props. does not contain or evolve formaldehyde during cure accepts high filler loads of calcium carbonate, clays, alumina trihydrate good aging props., wet tens, str., salt tolerance, adhesion to various fibers... 

These allow improved dispersion of fillers, especially useful when high loadings of alumina trihydrate are required for low smoke, halogen-free FR formulations. A small addition to the resin allows more filler to be added without increasing viscosity. 

Halogen-free compositions are often rendered flame-retardant by the incorporation of inorganic fillers, particularly alumina trihydrate (ATH) or magnesium hydroxide. Although these fillers are essentially nontoxic and relatively inexpensive, the high loadings necessary for effective... 

The continuing interest in changing the combustion characteristics of composites has focused attention on ATH (alumina trihydrate) filled high density polyethylene. Attempts to incorporate high loadings of ATH into HDPE normally leads to processing difficulties and degradation of composite properties. 

Alumina Trihydrate (Gibbsite) (Woycheshin, 1978) - Fine particle size 0.5 to 1.7pm) grades of this white filler can be used at high loadings in adhesives and sealants as a fire retardant. The filler is stable at temperatures below 205°C, decomposes slowly at 205 to 220°C and rapidly above 220 C to form aluminum oxide and water vapor. 

The disadvantages of alumina trihydrate are that it can not be processed at more than 205°C, and that the high loadings required for effective fire... 

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