Urethane fiber glass reinforcements

Kuyzin et al discussed a low-density SRIM made by using glass-fiber reinforcement and a urethane-modified isocyanurate foam system (26), or by using polyamide-coated polyester fibers and a urethane-modified isocyanurate-foam system (36). 

Schumacher and Slocum (7) presented papers regarding low-density urethane-foam composites to be used for automotive door trims. The physical properties of glass-fiber-reinforced urethane-foam composites are shown in Table 53. 

Polypropylene and nylon Reactive intermediate in making polyester and epoxy flame retardant resins Polyolefins, ABS, polyesters Thermosets and thermoplastics Urethane foams and polyesters Plastic foams and polyester fibers Thermoplastics usually as a synergist Engineering thermoplastics Glass reinforced nylon and PBT... 

Estaloc, Glass fiber-reinforced urethane elastomer, BFGoodrich Specialty Chemicals Estane, Polyurethane resins and compounds, BFGoodrich Specialty Chemicals Estoin, Polymer soluble dyes, Oariant Cotp., BU Additives... 

Narva, K.K., Lassila, L.V.J., and Vallittu, P.K. (2004) Fatigue resistance and stiffness of glass fiber-reinforced urethane dimethacrylate composite. J. Prosthet. Dent., 91 (2), 158-163. 

Many different thermosetting polymers are used in pultmsion, eg, polyester, vinyl ester, epoxy, and urethane. Reinforcements must be in a continuous form such as rovings, tows, mats, fabrics, and tapes. Glass fibers are the low cost, dominant composition, but aramid and carbon fibers are also used. 

The chassis is made from a 1/4 in. sheet of either ABS or TPO vacuum formed into a tub and reinforced with reinforced pultruded glass fiber-TS polyester plastic tubing. The hood and other products are being made from a 20 mm thick sandwich of thermo-formed PPO-alloy skins, glass fabric infused with thermosetting vinyl ester, and a urethane foam core. The bumper and front fascia is thermoformed from a polyolefin elastomer sheet with an UV-resistant cap layer of DuPont s Tediar PVF film. The dash and... 

Isham, A.B., Glass Fiber-Reinforced Elastomers for Automotive Applications—A Comparison of RIM Urethanes and Alternate Material Systems, Soc. Autom. Engl Meet., Preprint No. 760333, Feb. 1976. 

The matrix resins for foamed composites include rigid pol)ruretha-nes, unsaturated polyesters, vinyl esters, and their hybrid resins, such as, unsaturated polyester-urethane hybrid resins and vinyl ester-urethane hybrid resins. The reinforcing fibers include glass fibers, carbon fibers, and organic fibers such as polyamide fiber (Kevlar, DuPont), polyamide-... 

Table XI demonstrates the effect of fiber length on properties for a type of RIM processable material - the urethane modified isocyanurate which has low impact. Table XI ccnpares milled glass fibers with 1/8" chapped strand. The longer aspect length chopped strand provides for true reinforcement. However, it cannot be used in current RRIM equipment.

Reinforced RIM urethane using milled glass fibers (1/16 ) at 25% loading or more is now the "state of the art" reinforcement. 

Surface Quality. Class "A surface (after painting) is considered by the automotive industry as their first requirement for an exterior part. Comparing the surface quality of several reinforcements in RRIM urethane panels, it was found by visual examination that the best surface quality was the glass flakes and the worst was the integral chopped strands. Milled fiber is slightly worse than glass flakes, but it is still considered a "Class A" surface. 

Impact Strength. Figure 6, notched Izod impact strength, shows one of the main reasons for the interest in chopped integral strands (c/s) as RRIM urethane reinforcement. The nonreinforced urethane polymer used in this study had an impact value of approximately 12 ft-lb/in. Reinforcement with 20% milled glass fibers lowers this value to about 5 ft-lb/in. (Column B). 

This process, in which a high modulus urethane elastomer is reinforced by milled glass fibers is currently commercially used in a three piece air spoiler used on the 1980 Pontiac Sunbird. The first use of reinforced RIM urethane front fenders is scheduled for use on a 1981 model car. 

Uses Adhesion promoter for filled and reinforced resins (urethanes, epoxies, acrylates, phenolics), adhesives, sealants, coatings, glass fiber sizes and finishes, primers, and foundry sand binders Features Improves high-temp, resist., increases stability of resin/silane bond at high temps. 

N nylon, PO polyolefin, elastomer, TPU thermoplastic urethane, GF glass fiber, NBR nitrile rubber, MAH maleic anhydride, EPR ethylene-propylene copolymer, l ionomer, M- mineral, ABS acrylonitrile-butadiene-styrene copolymer, PPE poly (phenylene ether), R reinforcement, PTFE poly(tetrafluoroethylene), CF° carbon fiber, PEBA poly(etherblockamide), S silicone, RIPP D reaction injection molding plastic, and ASA acrylate-styrene-acrylonitrile copolymer. 

Other tertiary recycling processes that have been developed include a Freeman Chemical Corp. process to convert PET bottles and film to aromatic polyols used for manufacture of urethane and isocyanurates. Glycolized PET, preferably from film, since it is often lower in cost than bottles, can be reacted with unsaturated dibasic acids or anhydrides to form unsaturated polyesters. These can then be used in applications such as glass-fiber-reinforced bath tubs, shower stalls, and boat huUs. United States companies that have been involved include Ashland Chemical, Alpha Corp., Ruco Polymer Corp., and Plexmar. Unsaturated polyesters have also been used in polymer concrete, where the very fast cure times facilitate repair of concrete structures. Basing polymer concrete materials, for repair or precast applications, on recycled PET reportedly leads to 5 to 10 percent cost savings and comparable properties to polymer concrete based on virgin materials. However, they are still approximately 10 times the cost of portland cement concrete. There appears to be little commercial application of these processes at present. 

Figure 6-20. A dock box made of a TS polyester-urethane hybrid glass-fiber-reinforced material to meet demands for durability and toughness.

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