Preparation Of Degradable Polymer Materials By Plant Oils

Nowadays, polymers and polymeric composites are derived from petroleum reserves, and these petroleum-materials are not environmental mostly and their manufacture procedure is complicated. There is a growing interest to produce biopolymers. Triglyceride oils are one of the most important sources for biopolymers. Oil-based biopolymers have many advantages compared with polymers prepared from petroleum-based monomers. They are biodegradable and, in many cases, cheaper than petroleum polymers. The polymers ranging from elastomers to tough and rigid plastics were prepared by the free-radical suspension and emulsion copolymerization of plant oil with styrene. The research of the theme is as follows:1 Free-radical suspension copolymerization of soybean oil with styrene was studied. The FT-IR results reveal that soybean oil and styrene were copolymerized. According to NMR analysis soybean oil can get up to 6.45% by weight percentage in the resulting copolymer. In addition the influence, which contains the polymerization temperature, the polymerization time, the suspension reagent variety and dosage and the initiator reagent variety and dosage on copolymer molecular weight and copolymer compositions, was analyzed. And the soybean oil content's influence on the copolymer molecular weight, gelatin percentage and copolymer compositions was researched. The glass transition temperature of the copolymer was about 73.1℃by differential scanning calorimetry (DSC), which proved that the ester group attached to the soybean oil-styrene copolymer chains improved the flexibility. The triglyceride content can be calculated from the thermal gravity (TG) results.2 The cross-linking polymer was copolymerized by the free-radical suspension copolymerization of the tung oil and styrene. The FT-IR results reveal that the tung oil and styrene were copolymerized. The gelatin in the copolymer went up to more than 95% as the tung oil increased. The results showed that the triglyceride could reach 1.05% in the copolymer at most. Because of the conjugated bonds, the tung oil is more activated than the soybean oil.3 In order to enhance the molecular weight and tensile properties, the emulsion copolymerization of the soybean oil and styrene was researched. Orthogonal experiment was designed, which concluded the influence of the temperature, time, initiator and the soybean oil content on the molecular weight and the copolymer compositions, for the purpose of finding out the optimization conditions.