| Free-radical polymerization of styrene was carried out in the presence of a series of peroxide initiators. The objective of this paper was to investigate the chemical structure of styrene oligomer and measure its concentration.The results were compared by using Trigonox 21S, Trigonox C, JWEB50 as initiators at equivalent molar concentrations and different temperatures and time in the polymerization of styrene. Viscosimetry, GC and GC-MS have been used to measure viscometric average molecular weight, oligomer concentration and oligomer structure. Compared with monofunctional initiator and tetrafunctional initiator, the results are easily achieved that molecular weights is higher for the tetrafunctional one. We can also conclude that tetrafunctional initiator caused the conversion rate to be faster than that with monofunctional initiators.Superabsorbent is a new type of macromolecule materials which appeared in 1960s. Superabsorbents can absorb a large amount of water compared with general water-absorbing materials, in which the absorbed water is hardly removable even under some pressure. However, slow water-absorption rate and poor anti-salt property have remained the main disadvantages of superabsorbent.In this paper, poly(acrylic acid) superabsorbents were synthesized by using metal ions as crosslinking agents. The synthetic variables(temperature, the monomer concentration ,crosslinker concentration, initiator concentration, neutralization degree) were also studied. Poly(acrylic acid) superabsorbent also can be prepared by microwave. Tungstate and styrene are added respectively when synthesizing poly(acrylic acid) superabsorbents.Experiment results indicate that the synthetic condition affects the properties of superabsorbents. Superabsorbent added tungstate shows a better salt-resistance. The water-absorption rate was enhanced by using microwave. The water retention and salt-resistance were also improved by adding styrene when preparing poly(acrylic acid) superabsorbent.
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