Reinforced plastics filled systems

Table 11 indicates that syntactic plastics are similar in strength properties to monolithic filled systems (glass-reinforced plastics), although their apparent densities are 2-3 times smaller. Hence, syntactic plastics appear to have the highest specific strengths of all known plastic materials. 

Time-temperature superposition works for homopolymers and miscible blends but not for immiscible blends, filled systems (e. g., glass fiber reinforced plastics) or reactive or unstable polymers. 

This change can be attributed to the fact that the composition of the system during the second hour has changed markedly from what it was earlier. It is now, in a sense, a network-reinforced plastic, in which the network consists of crosslinked partly dehydrochlorinated polymer, and the interstices are filled with relatively undegraded polymer. 

These types of microheterogeneity are inherent in all polymer systems, filled with particulate and fibrous fillers, in two-phase and multi-phase polymer systems (mixtures of polymers with discrete and continuous distribution of components), as well as in polymer glues, coatings, fiber-reinforced plastics, i.e., in all polymer composites. However, in polymers with mineral reinforcement, microheterogeneity appears as a result of interfacial phenomena only in the... 

The data presented here have been selected with the aid of the RAPRA database on reinforced plastics and composites, from commercial trade literature and sources, from the composites literature and the authors and their colleagues private sources. We have always tried to select information on well-prepared and described systems using modern fibre types and matrices. Inevitably it has not always been possible to do this and in some cases we have had to use older data, information where the fibre or resin is not fully specified or material for other than unidirectional systems. In doing this we have had to balance the need for information with the uncertainties mentioned, but where we have done this we believe that the information quoted, though not ideal, is the best way of filling a real gap. 

A number of examples of reinforced or filled polymer systems are shown in Table 6. As a general rule, as the thermal conductivity or the amount of the non-polymeric phase increases, so does the thermal conductivity of the composite. Examples listed in Table 6 include glass-reinforced polycarbonate and pol3Kethylene terephthalate), and mica-filled epoxy resins. On the other hand, plasticizers... 

In the reinforced RIM (RRIM) process a dry reinforcement preform is placed in a closed mold. Next a reactive plastic system is mixed under high pressure in a specially designed mixing head. Upon mixing, the reacting liquid flows at low pressure through a runner system to fill the mold cavity, impregnating the reinforcement in the process. Once the mold cavity is filled, the plastic quickly completes its reaction. The complete cycle time required to produce a molded thick product can be as little as one minute. 

Disperse oxides unmodified or modified by organics (OC) or OSC are used as fillers, adsorbents, or additives [1-11]. OSCs are used as promoters of adhesion, inhibitors of corrosion, for the stabilization of monodisperse oxides and the formation of the nanoscaled particles. Oxide modification by alcohols or other OC is of interest for synthesis of polymer fillers, as such modification leads to plasticization and reinforcement of the filled coating, but in this case a question arises about hydrolyz-ability of the =M—O—C bonds between oxide surface and alkoxy groups, as those are less stable than =M—O— M= formed, for example, upon the silica modification by silanes or siloxanes. The high dispersity, high specific surface area, and high adsorption ability of fumed oxides have an influence on their efficiency as fillers of polymer systems. 

This Landolt-Bomstein book, Volume Vlll/6, provides a compilation of quantitative parameters craicem-ing thermomechanical, mechanical and fracture-mechanical properties of pure, filled and reinforced thermoplastics, thermosets and high-performance composites. Because there has been very rapid and dynamic progress in this field of research, and because of the enormous growth rates of the available material systems in plastics production and use, it seemed appropriate to review the data currently available in the literature from a systematic perspective. 

A Guillet. Organosilicon coupling systems for filled and reinforced polyolefins. SPE Technical Conference, Filler and Additives in Plastics, Goeteborg, November 1986. 

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