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CHEMICALS
Reinforced plastics find use in such things as these airplane tail cones shown o n an aircraft assembly line
Better Resins for Better Plastics Reinforced plastics industry reaps benefits from new resins with weatherability, h e a t resistance JLJESPITE THEIR GREAT VERSATILITY,
reinforced plastics still need improving. Potential uses are being stymied by the failure of these materials to meet rigid performance demands. What's needed are materials with improved weathering properties, greater fire resistance, higher temperature resistance, im proved flow, better impact strength, greater chemical resistance, and more rapid cure times. But, of course, the reinforced plastics industry hasn't been standing idly by. T h e past year has brought forth a num ber of new or improved resins that are helping to meet the challenges of this jet-atomic-rocket-satellite age. Special stress is being placed on plas tics with improved heat resistance, Johan Bjorksten, president of Bjorksten Research Laboratories, told the meet ing of the Society of the Plastics In 60
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dustry's Reinforced Plastics Division. In particular, fire resistance is needed in the building field. High tempera ture resistance is essential in many mili tary applications. It's also becoming more important in the electrical indus try, where larger and larger amounts of power are being concentrated in smaller and smaller devices. For fire resistance, Hooker Electrochemical's Hetron resins, based on endomethylenetetrahydroh e x a c h l o r o phthalic anhydride, have gained a unique position, says Bjorksten. One of the new products, Hetron 33, which is recommended for sheeting and build ing applications, can withstand paint bake cycles without crazing. Hetron 103, a resin for the aircraft industry, combines fire resistance with good strength retention at high temperatures. Barrett's Plaskon 9121, a diallyl
phthalate monomer resin, has a heat distortion temperature above 390° F. For use at higher operating tempera tures, about 500° F., the resin 37-9X, made by Cincinnati Testing Labora tories, is claimed to hold u p under thermal shocks even greater than the deformation temperature of Ε glass. This new phenolic silane resin, says Bjorksten, is bound t o accelerate the development of new glass fibers capa ble of withstanding unusually high temperatures. It's already being used in several classified missile applications. Union Carbide's silicones division has come up with a low viscosity, 100% reactive vinyl silicone called XR-70. It should be especially useful for the low pressure construction of high tem perature laminates. Unlike polyesters, it can withstand temperatures greater than 350° F. The n e w Selectron resins 5156A and 5140, made b y Pittsburgh Plate Glass, are effective in reducing curing times. D o w Coming's new resin 2105A has the virtue of maintaining its electrical strength at high temperatures. It should find considerable use in high grade electrical laminates and in mak-
A liquid simplifies handling Glycerine is s liquid. 3n making alkyds, there are no bags to lift, n o fines. A^s easily as opening a valve, Gly cerine can b e piped into your kettles. Too, you can measure it either by volume or weight. And as needed, it's easy and safe to addl more Glycerine during cooking. Glycerine has other important advantages in making alkyds: • Its simple molecular structure makes cooking easier.
• Its favorable combining weight makes a wide range of resin properties economically feasible. • Its chemistry has been thoroughly evaluated. Methods are perfected and literature abundant. Glycerine's usefulness continues to grow. Stable in price» dependable in supply, Glycerine offers a unique bal· ance of properties. We'd like to send you our 20-page booklet: "Glycerine Terms, Tests and Technical Data." Address your request to the Glycerine Producers* Association.
Properties HYGROSCOPICITY ·
STABILITY
SOLVENT POWER · ^VISCOSITY NONVOLATILITY · NO ^TOXICITY TASTE ·
COMBINING WEIGHT
Applications HUMECTANT · CARRIER SOLVENT ·
LUBRICANT
SOFTENER · EMOLLIENT ANTI-FREEZE · ALKYD BASE
GLYCERIM Ε PRODUCERS' ASSOCIATION · 2 9 5 MADISON AVENUE, NEW YORK 17, Ν. Υ. FEB.
17,
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CHEMICALS
LUCIDOL A New Catalyst for Room or Low Temperature Polymerization off Polyester Resins @£
S0.O% (min.) 6.2 5%(min.)
Ketone Peroxide # 6 Active Oxygen . · .
SP^CIF|CAT
