| The concept of physical crosslinking was introduced into the research field of oil absorption resin which was traditionally synthesized by chemical crosslinking. It was trusted that two problems for the absorption resin, the low ratio of oil-absorption and the irreversibility of oil-releasing, can be solved by thermoreversibility and long-time creep of physical crosslinking. PA was filled into oil absorption resin as physical crosslinker to construct a kind of three dimensional network with high crosslink degree and low crosslink density.The acrylic high oil absorption resins including partially physical crosslinking and totally chemical crosslinking were prepared by the suspension process. The effects of reaction temperature, speed rate, the ratio of water to oil, initiator and dispersant concentrations, monomer feed ratio, chemical and physical crosslinker concentrations on oil absorbency and gel fraction (crosslink degree) were studied. The recipe and operation conditions were optimized as follows: mass ratio of styrene (St) : functional monomer = 3:1, 0.5wt% initiator at 80 for 7-8 h. The effect of physical crosslinker (PA) concentration was complex. Oil absorbency increased with increasing PA at lower chemical crosslinker (CA) concentration. But, under this same condition, particles can not be formed if PA concentration was higher than a certain value. Differently, there was an optimum PA concentration when CA concentration was higher. Oil absorption speed was also investigated. The presence of PA can speed up the process of oil absorption for the acrylic high oil absorption resins.Dynamic mechanics method was used to characterize the properties of resin. It demonstrated that the quantity of physical crosslinking was increased by the introduction of PA. By studying the effects of temperature and quantities of CA and PA on storage modulus (G) and loss modulus (G ), we also found that the effect of physical crosslinking on G was light, but on G was strong. To resin crosslinked only by PA, there is a platform region with the increase of temperature because of the disentanglement of entanglement and the decrease of interactive force between chains. Similarly, the effects of the quantities of CA and PA on G were also complexed, and G was affected by both temperature and frequency.The swelling behavior of the samples was observed and recorded on line. It demonstrated that a kind of relaxing three-dimensional network was indeed formed by theintroduction of PA. The effects of monomer feed ratios, crosslinking agent concentration and type, particle size and temperature on oil absorbency and oil absorption speed were investigated. Results indicated that there were an optimum monomer feed ratio and an optimum amount of CA or PA. In addition, particle size and temperature had much serious influence on oil absorption speed in comparison with monomer feed ratio and crosslinking agent concentration and type. Results also showed that particle size affects oil absorbency to a great degree and the effect of temperature on oil absorbency was complex.The oil absorption rate and optimized ratio of two monomers as well as gel fraction in two kinds of different resins were compared. The oil absorption properties of two kinds of different resins produced from monomer with low affinity to oil and effects of the quantity of chemical crosslinking agent on them as well as the effects of temperature on G and G were compared. Results indicated that the introduction of physical crosslinking would improve the oil-absorption properties, including raising oil absorption rate and increasing oil absorbency of resins produced from monomer with low affinity to oil. In addition, it complexed the variation of gel fraction and increased the quantity of monomer with low affinity to oil in optimized ratio of monomer. Results also indicated that partially physical crosslinking resins had a best amount range of chemical crosslinking agent, and with the increase of temperature, G and G of partially physical crosslinking res...
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