摘要:
Resins prepared by cationic polymerization of pure or combined feeds of C.sub.5 -C.sub.10 hydrocarbons are decolorized by use of iodine or bromine or their compounds. Activation by heat or radiation is usual. The decolorizing agents may be added prior to or during the polymerization process or to the polymerized resin before or after isolation.
摘要:
The specification discloses a method for esterifying rosins with a polyol which comprises contacting rosin with the polyol in the presence of a bleaching mixture which includes both an alkaline earth hypophosphite and hypophosphorous acid and, preferably also, an organic sulfide, under esterification conditions to produce a rosin ester. The method enables production of rosin esters which have a color of less than about 5 Gardner neat. The preferred bleaching mixture includes from about 0.01% to about 0.10% of the alkaline earth hypophosphite and from about 0.10% to about 0.15% of active hypophosphorous acid, where the amounts are based on the weight of the rosin. The most preferred alkaline earth hypophosphite is calcium hypophosphite. The specification also describes a method for preparing an adhesive from the rosin ester.
摘要:
Glycerol esters of modified rosin are useful tackifiers in rubber adhesive compositions. Esters made with rosin modified by reducing the abietic acid concentration to 5% or less, will retain tackifying properties for longer periods in storage before use. The esters are prepared by simultaneously disproportionating and esterifying unmodified rosin with glycerol in the presence of p-t-amyl phenol and phosphoric acid, for example.
摘要:
Reduction of dust formation for particleized resin is achieved by adding low density high molecular weight polyethylene to molten resin at a temperature and under conditions sufficient to cause the polyethylene to become dispersed within the resin. The resin/polyethylene mixture is then formed into solid particles. The addition of low density, high molecular weight polyethylene significantly reduces the generation of dust during handling, such as in the particleizing and packaging stages of the manufacturing process, while providing resin particles with higher effective softening points as compared to resin particles augmented with polyethylene wax.
摘要:
A novel copolymer resin which has excellent tackifying properties for selected elastomers useful in hot melt and pressure sensitive adhesives is produced by the copolymerization of beta-pinene with other terpenes or hydrocarbon monomers, followed by thermal catalytic isomerization of the resin produced. Typically, beta-pinene and styrene (80/20) are copolymerized at a temperature between 0.degree. to 60.degree. C. under anhydrous conditions with a Lewis acid catalyst in a solvent. After catalyst removal, the copolymer resin is isomerized with iodine as a catalyst at a temperature between 200.degree. to 260.degree. C. Excellent yields of high softening point tackifier resins are produced.