天然橡胶防腐衬里自然硫化胶料的研制

简要介绍天然橡胶防腐衬里自然硫化胶料的基本配方、衬里的施工工艺及胶粘剂的情况。     

Influence of oil contents in dynamically cured natural rubber and polypropylene blends

Mechanical, dynamic, thermal, and morphological properties of dynamically cured 60/40 NR/PP TPVs with various loading levels of paraffinic oil were investigated. It was found that stiffness, hardness, tensile strength, storage shear modulus, complex viscosity, glass transition temperature (T_g) of the vulcanized rubber phase, degree of crystallinity and crystalline melting temperature (T_m) of the polypropylene (PP) phase decreased with increasing loading levels of oil. This is attributed to distribution of oil into the PP and vulcanized rubber domains causing oil‐swollen amorphous phase and vulcanized rubber domains. An increasing trend of elastic response in terms of tension set and damping factor was observed in the TPVs with loading levels of oil in a range of 0–20 phr. It is supposed that a major proportion of oil was first preferably migrated into the PP phase and caused an abrupt decreasing trend of degree of crystallinity and T_m of the PP phase. The dispersed vulcanized rubber domains remained small as particles with a low degree of swelling. Increasing loading levels of oil higher than 20 phr caused a decreasing trend of elongation at break and elastomeric properties. Saturation of oil in the PP phase was expected and the excess oil was transferred to the rubber phase which thereafter caused larger swollen vulcanized rubber domains. The remaining amount of oil was able to separate as submicron pools distributed in the PP matrix. This caused lowering of T_g, T_m, crystallinity of PP phase as well as strength, elastomeric, and dynamic properties of the TPVs. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

用刚度来判定压缩型减振橡胶产品的硫化时间

研究了不同硫化时间对压缩型减振橡胶产品刚度的影响规律。结果表明,在硫化过程中,产品刚度随硫化时间的延长逐渐增大,达到最大刚度后,继续增加硫化时间,产品刚度逐渐下降。压缩型减振产品生产用硫化时间通过产品刚度的测定,以产品达到最大刚度的时间作为产品生产的硫化时间。     

抗硫返原剂对NR体系性能的影响

研究了两种抗硫返原剂KE7699、TP50对纯NR复合体系力学性能、生热性能、压缩永久变形性能的影响。研究表明:在NR的硫磺硫化体系加入一定量的KE7699、TP50后,胶料的焦烧时间缩短,硫化速度加快。硫化胶的拉伸强度等力学性能都有所降低,胶料的压缩生热和永久变形降低。两种抗硫返原剂相比,TP50在老化后力学性能保持率、动态生热等方面要优于KE7699。     

不同调控措施下烤烟开花时间与碳氮代谢关系的研究

通过田间试验对不同调控措施下烤烟开花时间进行了研究。结果表明,与对照相比,各处理均能推迟烤烟开花时间,增加有效叶片数,提高烟叶产质量;4个处理能明显提高叶绿素含量、NR活性和淀粉酶活性,增强烟株前期氮代谢,有利于个体形态构建,同时进入旺长期后可以使淀粉酶活性缓慢上升,抑制其过早进入生殖生长,使碳氮代谢更协调,从而达到控制和推迟早花的目的。     

胶料介电特性的全填充短路波导测试和分析

采用微波测试法中的全填充短路波导测试法测试炭黑胶料硫化过程中介电特性———介电常数εｒ和介电损耗因子ｔａｎδ的变化。测试分析结果表明,随着胶料交联密度增大,εｒ增大;炭黑粒径越小、比表面积越大、结构越高,胶料的ｔａｎδ越大;同一硫化条件下,ＮＲ、ＢＲ、ＳＢＲ、充油顺丁橡胶和充油丁苯橡胶胶料的εｒ顺次减小。     

一种新型橡胶填料—改性膨润土

介绍了改性膨润土在基础胶天然橡胶 (NR)和丁苯橡胶 (SBR)及橡胶制品轮胎当中的应用 ,结果表明 :(1)在NR和SBR中加入 10份改性膨润土不影响硫化胶的力学性能 ;(2 )在轮胎中加入 5～10份改性膨润土不但不影响轮胎半成品的力学性能 ,而且提高了橡胶与帘线的粘接强度 ;(3)改性膨润土易与SBR相混合。     

偶联剂Si69对乳液共沉法生成白炭黑/NR复合材料性能的影响

研究偶联剂Si69对乳液共沉法生成白炭黑/NR复合材料性能的影响.结果表明,在乳液共沉法生成白炭黑的反应中加入偶联剂Si69,可以增强白炭黑粒子与NR基体之间的界面作用,改善白炭黑在NR中的分散状态,提高复合材料的物理性能和混炼胶的动态力学性能;偶联剂Si69的适宜用量为3份.     

稀土丁戊橡胶性能及在胎面胶中应用的研究

通过与俄罗斯丁戊橡胶和BR对比 ,研究了国产新型稀土丁戊橡胶 (Nd BIR)的加工性能、未硫化胶性能和硫化胶物理性能 ,并探讨了Nd BIR在轮胎胎面胶中的应用。结果表明 ,Nd BIR混炼包辊性好 ,混炼功耗低 ,混炼胶片表面光滑平整 ;胶料硫化速度快 ,硫化曲线平坦 ,门尼焦烧时间长 ;硫化胶撕裂强度高 ,耐疲劳、耐磨耗和耐老化性能好 ,压缩生热低 ,低温性能极佳。NR/Nd BIR(并用比 70 /3 0和 5 0 /5 0 )并用体系胎面胶硫化速度快 ,焦烧时间长 ;硫化胶强伸性能好 ,耐磨、耐老化、耐疲劳和抗湿滑等性能满足轮胎胎面要求。Nd BIR用于轮胎胎面胶中是可行的     

改性纳米硫酸钡在NR/BR并用胶中的应用

研究改性纳米硫酸钡对NR/BR并用胶性能的影响.试验结果表明,采用改性纳米硫酸钡部分替代炭黑,NR/BR并用胶的焦烧时间和正硫化时间延长,加工性能和耐热空气老化性能良好,耐屈挠性能优异,滞后损失和生热较低.