离子交换层析分离－EDTA法测定硫化胶中的Ca~(2 )、Mg~(2 )、Zn~(2 )

用离子交换树脂分离硫化胶中的Ｃａ~（２＋）、Ｍｇ~（２＋）、Ｚｎ~（２＋）等共在离子，以便消除组液时的互相干扰，用常规法依次测定。不用加入掩蔽剂，避免了常规法在测定它们时使用的剧毒化学试剂──氰化钾（ＫＣＮ）作为掩蔽剂而对操作者及环境所带来的危害。     

橡胶的微观结构与硫化胶还原相关性

本文从橡胶微观结构角度讨论了丁二烯、苯乙烯、异戊二烯类柔曲型高聚物系列对硫化返原的影响。用硫化仪来测定系列的硫化胶返原性,以探讨橡胶的微观结构与硫化返原关系,并从分子理论方面加以解释。     

Preparation of interfacially compatibilized PP‐EPDM thermoplastic vulcanizate/graphite nanocomposites: Effects of graphite microstructure upon morphology,electrical conductivity,and melt rheology

Electrically conductive PP/EPDM dynamically crosslinked thermoplastic vulcanizate (TPV)/expanded graphite (EG) has been successfully prepared via melt compounding of maleic anhydride grafted polypropylene (PP‐g‐MA)/EG masterbatch and a commercially available TPV material. Correlation between graphite microstructure, and electrical conductivity as well as melt rheological behavior has been studied. Natural graphite flake (NGF), graphite intercalated compound (GIC), and exfoliated graphite (EG) have been employed and compared. Scanning electron microscopy (SEM) showed the presence of 100–200 nm nanolayers in the structure of PP‐g/EG masterbatches, whereas thinner platelets (1.5–2.5 nm) were revealed by transmission electron microscopy (TEM). Better dispersion of the graphite nanolayers in the microstructure of TPV/PP‐g‐MA/EG composite was verified, as the 7.3 Å spacing between the aggregated graphite nanolayers could not be observed in the XRD pattern of this material. TPV/PP‐g/EG nanocomposites exhibited much lower conductivity percolation threshold (φ_c) with increased conductivity to 10^?5 S/cm at EG wt % of 10. Higher nonlinear and nonterminal melt rheological characteristics of dynamic elastic modulus (G′) at low frequency region was presented by the TPV/PP‐g/EG nanocomposites, indicating the formation of nanoscopic conducting multiple networks throughout the continuous TPV matrix. Maleated PP was found to be much more effective in separating EG nanolayers which is attributed to the higher interfacial interaction between PP‐g‐MAH and EG, synergized with its multiporous structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

增容剂对硅橡胶/热塑性聚氨酯热塑性硫化胶性能的影响

采用动态硫化法制备了甲基乙烯基硅橡胶（MVQ）/热塑性聚氨酯（TPU）共混型热塑性硫化胶（TPV）,考察了增容剂的种类及用量对TPV力学性能及加工流变性能的影响。结果表明,随着增容剂用量的增加,TPV的力学性能呈先上升后下降的趋势。相比于乙烯丙烯酸共聚物和乙烯与乙酸乙烯嵌段共聚物,用聚烯烃弹性体接枝马来酸酐（POE-g-MAH）作为增容剂时TPV的力学性能更为优异。3种增容剂均能提高TPV中MVQ相与TPU相的相容性。当POE-g-MAH的用量为6份时,TPV中MVQ相与TPU相的玻璃化转变温度靠近程度最大,两相界面较为模糊,增容效果最佳。     

不同硫化体系对环保型硬丁腈橡胶性能的影响

以松香酸皂与油酸皂组成的复合乳化体系制备的中试产品丁腈橡胶(NBR)为基胶,分别用硫黄体系和过氧化物体系进行硫化,研究了NBR混炼胶的硫化特性和硫化胶的物理机械性能、耐老化性能、耐油及耐寒性能,并与传统产品NBR 3604进行了比较。结果表明,采用硫黄体系时,NBR混炼胶的硫化程度较浅,硫化速率较慢;采用过氧化物体系时,NBR混炼胶的硫化程度较深,硫化速率较快,NBR胶料宜采用过氧化物硫化体系进行硫化;2种硫化体系下制得NBR硫化胶的物理机械性能与NBR3604硫化胶相差不大,过氧化物硫化体系制得NBR硫化胶的耐老化性能较好;与NBR 3604硫化胶相比,2种硫化体系下制得NBR硫化胶的耐寒性稍好,耐油性稍差。     

纳米碳酸钙/二氧化硅复合粒子的制备及其在丁苯橡胶中的应用

将纳米碳酸钙的制备和表面包覆工艺融为一体,以硅酸钠为无机硅源,采用溶胶沉淀法制备出具有核壳结构的纳米碳酸钙/二氧化硅复合粒子,在纳米碳酸钙的表面包覆了一层致密的二氧化硅膜。采用TEM、红外光谱（FT-IR）、TG、XRD、BET、吸油值测定等手段对复合粒子的大小、形貌、化学组成、结构及表面性质进行了分析和表征。将复合粒子填充于丁苯橡胶,能显著提高丁苯橡胶（SBR）硫化胶的拉伸性能和撕裂性能。当填充量为75份时,拉伸强度最大,为13.6 MPa。     

高性能氢化丁腈橡胶的配方与性能

在加氢度为96％、结合丙烯腈质量分数为34％的氢化丁腈橡胶(HNBR)中,以2,5-二甲基-2,5-双(叔丁基过氧基)己烷为硫化剂,三烯丙基异氰脲酸酯(TAIC)为助硫化剂,分别加入不同牌号的炭黑[N330,N539,N550,半补强炭黑(SRF)或喷雾炭黑],于180℃下硫化15min,制备了具有低压缩永久变形、优异力学性能的HNBR硫化胶。结果表明,增加硫化剂用量,以及在其较小用量下添加TAIC时,可降低HNBR硫化胶的压缩永久变形。对不同牌号炭黑增强硫化胶综合性能的分析可知,在硫化剂用量为6．25份(质量,下同),TAIC用量为1．25份时,炭黑对HNBR硫化胶增强效果由大到小为：N330,N539,N550,SRF,喷雾炭黑。     

复合硫化剂硫化NR的压缩疲劳及动态粘弹性能

研究了以双－１,６－（二乙基硫代氨基甲酰）二硫化己烷和硫黄为复合硫化剂硫化ＮＲ的压缩疲劳性能与动态粘弹性能。实验结果表明,复合硫化剂硫化ＮＲ与硫黄硫化ＮＲ相比,前者具有较低的生热和ｔｇδ值,较长的疲劳寿命及较高的杨氏模量。     

指数函数模型拟合NR／顺丁橡胶硫化胶疲劳断裂曲线

采用指数函数模型λ＝ＡｅｘｐＢｌｏｇＮ拟合４种不同配方ＮＲ／顺丁橡胶硫化的疲劳破坏曲线,结果表明,计算值与实测值吻合良好,相对偏差为－２．８３％－２．８９％,且分布较均匀,相关系数为０．９９６６－０．９９９５。