Polyesters, TS

The term TS polyester covers a very large chemical family, of which the unsaturated resins (covering orthophthalic, isophthalic, vinyl esters, and blends) form the largest single group of fiber reinforced TSs (RTSs). Polyesters offer a good balance of mechanical, electrical and chemical-resistance properties, at relatively low cost (Table 3.15). They also have good dimensional stability and are relatively easy to handle. They are 

Composite Tensile strength, psix ICP(MPa) Flexural strength, psix ICP (MPa) Flexural modulus, psix loF(GPa)  

General purpose Rigid moidings, craze resistant 

Light stable and weather resistant Chemical resistant 

good impact resistance, high flexurai strength, low flexural modulus 

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Fig. 6-14 specific modulus = modulus/density. Plastics include use of the heat-resistant TPs such as the polimides, polyamide-imide, and others. Table 6-21 provides data on the thermal properties of RPs. To date at least 80 wt % are glass fiber and about 60 wt% of those are polyester (TS) type RPs. 

POLYESTER(TS) POLYETHYLENE A COPOLYMERS POLYIMIDE MELAMINES POLYPHENLENE SULFIDE... 

Different materials can be used such as nylon, polyester (TS), and epoxy, but TS polyurethane (PUR) is predominantly used. Almost no other plastic has the range of properties of PUR. Modulus of elasticity range in bending is 200 to 1,400 MPa (29,000-203,000 psi) and heat resistance from 90 to over 200°C (122-392°F). The higher values are for chopped glass-fiber-reinforced RIM (RRIM). 

Saturated polyester (TS polyester) Thermoplastic polyesters Polybutylcne terephthalate (PBT) Polyethylene terephthalate (PET) Unsalurated polyester (TS polyester)... 

Epoi compounds were discovered by Prileschaiev in 1909, but its importance was realized only during WW-2. In 1956, glass fiber reinforcements were introduced. The thermoset polyesters (TS) were developed by Elhs in 1933-4. The first use of glass-reinforced TS dates from 1938. 

The workhorse of the RTS industry is TS polyester (also called polyester-TS) with glass fiber. The fiber reinforcement may be in the form of chopped fibers, porous nonwoven mats, woven fabrics, or continuous fibers. The combination of plastics and reinforcements results in versatile materials with unusual characteristics. The reinforcement adds strength and toughness to inherent weather resistance, moldability, and colorability. Thus RTSs are used because of their increased tensile, flexural, torsional, and impact strengths increased modulus of elasticity increased creep resistance reduced coefficient of thermal expansion increased thermal conductivity and, in many cases, lower costs. 

Recovery of expensive solvents is an attractive proposition, and there is a range of equipment suited to various requirements. Details are presented in Chapter 3 Polyesters, TS, TS Polyester Solvents. 

Underwriters Laboratories United Nations unsaturated polyester (TS) unreinforced plastics ultraviolet volt... 

Molds can range from hardwood for short runs to filled and unfilled high temperature polyester (TS) and epoxy resins, cast solid urethane, sprayed metal, cast aluminum, cast porous aluminum, and machined steels. The... 

The terms reinforced plastics (RP) and composites refer to combinations of plastic materials and reinforcing materials, usually in fiber form (chopped fibers, porous mats, woven fabrics, continuous fibers, etc. see Fig. 7-1). Both thermoset (TS) and thermoplastic (TP) resins are used. When modern RP industry started in 1940, glass-fiber-reinforced unsaturated polyester (TS), low pressure or contact pressure, curing resins were used. Today about 60 percent of the plastics industry uses many different forms of glass fiber-polyester composites. In this chapter the abbreviation RP will be used, and in references to polyester resin it will refer only to TS, as relatively little TP polyester is used in RPs. 

Based on SPI Composites Institute data on U.S. production of composites, in 1987 about 560,000 lb of the total of 2,536,000 lb of composites produced were reinforced TPs. The total figure includes all types of reinforcements and resins. At least 80 percent of composites were glass fiber reinforced, and 60 percent were polyester (TS) types. 

An SMC is a reinforced plastic compound in sheet form. Most SMCs combine glass fiber with a polyester (TS) resin. Any combination of reinforcement and resin can be produced. The reinforcements can have continuous long fibers or any size of chopped fibers laid out in a different orientation from that of the resin. The different orientation makes it feasible to use SMCs on flat to complex-shaped molds. These SMCs will contain various additives and fillers to provide a variety of processing and performance properties (Table 6-1). 

Table 7-4. Characteristics of Glass Fiber Reinforced Polyesters (TS).

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