Toughened thermoplastics composition

Deyrup, E. J., Toughened thermoplastic polyester compositions, US Patent 4 753 980 (to DuPont Company, Wilmington, DA), 1988. 

Chorvath I et al. (2001) Silicone rubber-toughened thermoplastic resin composition. WO Patent 2001018 116... 

In Table 7, typical key laminate properties for thermoset and thermoplastic composites are given. It is immediately apparent that suitable toughening (discussed previously) can achieve superior compression after impact and comparable edge delamination... 

Wahit, M. U., Hassan, A., Mohd Ishak, Z. A., Rahmat, A. R., and Abu Bakar, A. 2006. Morphology, thermal, and mechanical behavior of ethylene octene copolymer toughened polyamide 6/poly-propylene nanocomposites. Journal of Thermoplastic Composite Materials 19 545-567. 

Thermoplastic olefin (TPO) compositions typically consist of an immiscible blend of an isotactic polypropylene mixed with a polyolefin elastomer that acts as an impact modifier. It is possible to toughen these compositions further by using ethylene-propylene, ethylene-octene or ethylene-hexene impact modifiers. 

A. L. Spliner, Thermoplastic Molding Compositions, U.S. Pat. 3,681,475 (1972). Acrylic latexes, some IPNs. Rubber-toughened PMMA compositions. 

Blends of isobutylene polymers with thermoplastic resins are used for toughening these compounds. High density polyethylene and isotactic polypropylene are often modified with 5 to 30 wt % polyisobutylene. At higher elastomer concentration the blends of butyl-type polymers with polyolefins become more mbbery in nature, and these compositions are used as thermoplastic elastomers (98). In some cases, a halobutyl phase is cross-linked as it is dispersed in the polyolefin to produce a highly elastic compound that is processible in thermoplastic mol ding equipment (99) (see Elastomers, synthetic-thermoplastic). ... 

Thermosets are generally used in advanced composites due to their excellent thermal and dimensional stability, high modulus, and good mechanical properties. Because thermoset resins are inherently brittle, however, some applications require improved fracture resistance. Toughening of thermosets has been achieved through various methods, such as incorporation of reactive liquid rubber [1-9], elastomer [10], or rigid thermoplastics [11-25], and IPN formation with ductile component [26]. 

In Secs. 13.2-13.3 the principles of toughening of thermosets by rubber particles, and the role of morphologies, interfacial adhesion, composition, and structural parameters on the toughening effect are analyzed. Section 13.4 is devoted to the use of initially miscible thermoplastics for toughening purposes. The effect of core-shell rubber particles is discussed in Sec. 13.5 and, in Sec. 13.6, miscellaneous ways of toughening thermosets (liquid crystals, hybrid composites, etc.), are analyzed. 

Both thermoset and thermoplastic resins and CF composites have been examined using microhardness techniques. The thermoset resin used was an epoxy, both with and without PA6 particles that served as a toughening agent. 

From the above discussion, the choice of both composition and cure schedule is essential in the successful reactive processing of a thermoset toughened by the separation of dispersed elastomeric or thermoplastic (spherical) domains during the curing reaction. The... 

Dr. Riew has presented more than 50 technical papers and holds more than 25 patents on emulsion polymers, hydrophilic polymers, synthesis and application of telechelic polymers, and toughened plastics for adhesives and composites. His latest research is in the synthesis, characterization, and performance evaluation of impact modifiers for thermosets and engineering thermoplastics. His research interests include correlating polymer chemistry and physics, morphology, engineering, and static and dynamic thermomechanical properties to the failure mechanisms of toughened plastics. 

This year s U.S. production of thermoplastics, thermosets, and synthetic rubber is expected to be 29 billion pounds. About 80% of this is based on only a few common monomers. To improve performance, the polymer industry rarely changes to a new, probably more expensive polymer, but instead it shifts from mere homopolymers to copolymers, polyblends, or composites. These three types of multicomponent polymer systems are closely inter-related. They are intended to toughen brittle polymers with elastomers, to reinforce rubbers with active fillers, or to strengthen or stiffen plastics with fibers or minerals. 

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