In this article,a star-shaped hydrogenated polyisoprene(Star-EP) was synthesized for use as a viscosity index improver in lubricants.Polyisoprene arms were firstly synthesized by anionic polymerization, followed by a linking reaction with divinylbenzene.The resulting polymer Star-EP with the hydrogenation degree of more than 98%was then obtained by the hydrogenation of star-shaped polyisoprene using nikel naphthenate/triisobutyl aluminum catalyst system.The effects of structures and molecule weights on viscosity index were studied,furthermore,the effects of structures and molecule weights on thickening ability and shear stability in base oil 150N(HG) were discussed.At last,the low temperature performance and high temperature high shear properties were evaluated.

Styrene-isoprene-butadiene terpolymer(SIBR) was synthesized by anionic polymerization,and its structure was characterized.The effect of N,N,N′N′-tetramethylethylenediamine(TMEDA),diethylene glycol di-methyl ether(2 G) and tetrahydrofuran(THF) as external additives on hydrogenation reaction of SIBR catalyzed with triisobutyl aluminium(simplified as Al)/nickel naphthenate(simplified as Ni) catalyst system(mole ratio of Al to Ni 5) was studied.The results showed that the SIBR with relative molecular mass 10×104,polydispersity index no more than 1.10 could be synthesized under the conditions of temperature 50 ℃,the mass fraction of styrene 25%,mass fraction of isoprene and styrene 75%(mass ratio the two 1/1),TMEDA/n-BuLi(mole ratio)1.5.The hydrogenation reaction of SIBR was milder,the regulation and control of hydrogenation degree was more effective when polar additives TMEDA,2 G and THF were added.In the range of additive levels in this study,the order of influencing SIBR hydrogenation degree from large to small for the three additives was TMEDA,2 G,THF.

Through polar modifier dipiperidinoethane in modes of one-step and two-step adding,the polybutadiene with mass fraction of 1,2-structure of 98.5% and the stereoblock polybutadiene with different block ratios were obtained by anionic polymerization respectively.And the two kinds of polybutadiene were hydrogenated by nickel catalyst to synthesize atactic poly(1-butene) and polyethylene-poly(1-butene) block copolymer,and the polymers were characterized.The results showed that the atactic poly(1-butene) had high stereoirregularity and its glass transition temperature(Tg)was-24.5——22.7 ℃.The polyethylene-poly(1-butene) block copolymer had Tg of poly(1-butene) at low temperature region and a melting endothermic peak of polyethylene at high temperature region,and the Tg and crystallinity increased with increasing the content of polyethylene block.

以环烷酸镍（简称Ni）/三异丁基铝（简称Al）为催化体系,对自制的苯乙烯-异戊二烯-丁二烯三元无规共聚物（SIBR）进行加氢反应,确定了加氢反应条件,并对氢化SIBR进行了表征。结果表明,Al/Ni（摩尔比）变化时,SIBR中聚丁二烯链段的1,2-结构比1,4-结构易于加氢,聚异戊二烯链段的3,4-结构比1,4-结构更易加氢;在催化剂用量为2 mg/g、Al/Ni为7、反应温度为60℃、反应压力为4 MPa的条件下,SIBR的最高加氢度可达98%;氢化SIBR的数均分子量和重均分子量均比SIBR略有增大,分子量分布亦略有变宽,但仍呈现窄分布的特点;SIBR中聚丁二烯链段和聚异戊二烯链段均已发生氢化反应,而苯乙烯链段基本不发生氢化反应,说明该催化体系具有较高的催化活性和选择性。

It reviewed the advances of the modification of high impact polystyrene by blending with general plastics,elastomers and engineering plastics.It also put forward to the conception of preparation of HIPS/PO alloy without compatibilizer,which possesses good compatibility and mechanical properties.