Multi-acrylate Polymer Foam Developed And Performance

There are mainly four parts in this dissertation: choice of solvent, sol-gel process, study of preparation and property of poly-(acrylate) foam, and study of doped poly-(acrylate) foam.In free-radical solvent polymerization system initiator activity, polymerization speed and polymer solubility were affected with solvent property such as transfer reaction and cage effect. With PETA as the monomer, poly-(acrylate) gelation was produced in different solvents and foam was prepared. The poly-(acrylate) polymer's solvent parameter was 19.0 which was decided through the method of the theoretical calculation and experiment. Solvents with phenyl and alicyclic group in molecule made the initiator "impassive" and they had fast polymerization speed, whereas solvents with ketone, alky halide, lipoid, ether and acylamide group in molecule made the initiator "active" and they had slow polymerization speed.By changing the ratio of oxygen volume to solution volume, we found that solvent easily separated out in sol-gel process since oxygen could expend most active free-radical which was brought from initiator. The solvent separation volume increased wit the decrease of the initiator concentration. Through inspecting solution viscidity, we got the result that polymerization speed had direct ratio with monomer concentration and inverse ration with square root of initiator concentration. In the moment of low conversion, monomer concentration had more effect on polymerization speed. The gel mechanical properties had a close relationship with polymer's crosslinkage. Gel strength and modulus increased with the increase of crossing consistency while gel elasticity decreased. With expansion vibration peak of oxygen-carbon double bond as internal standard, we knew that the conversion of carbon-carbon double bond was affected with oxygen when foam density was fewer than 50mg/cm3. When density was more than 50mg/cm3, the percent conversion was about 86%.With carbon dioxide super critical drying technique (36C, 80MPa), poly-(acrylate) foam was successfully produced. We got the real density by weight and volume of foam and found the difference between real density and theoretical density of foam decreased with the increase of monomer concentration. Through the method of gas adsorption and pressing hydrargyrum, we knew foam's specific surface area increased quickly and then had a good steadiness with the increase of its density. We also knew there were two different types of pore diameters. The size of one kind formed inside micro-gel particles was about 7 nano-meters and its structure characteristic unchanged with the increase of foam's density. The size of the other type formed between different micro-gel particles was from several nano-meters to several microns and it decreased with the increase of foam's density.The doped acrylate monomer was synthesized through the reaction between different crylic acid and halogenated phenylic acid. AE1, AE2 and AE3 were three different kinds of doped acrylate monomer, had more reaction activity with PETA than AE3 and the polymerization of poly-(doped-acrylate) foam was prepared with density as 50 mg/cm3, doped chlorine as 15%wt.