乙基硅橡胶硫化性能的研究

以二乙基硅橡胶生胶为基胶,双二五、双二四等4种过氧化物为硫化剂,研究了硫化剂种类、硫化条件对二乙基硅橡胶硫化性能及机械性能的影响。结果表明,使用双二四为乙基硅橡胶硫化剂得到的乙基硅橡胶性能最好,其最佳一次硫化与二次硫化条件分别为120℃×10 min、150℃×4 h。     

硫化发泡体系对硅橡胶泡沫材料应力松弛性能的影响

考察了过氧化二异丙苯/N,N-二亚硝基五次甲基四胺(DCP/H)、2,5-二甲基-2,5-二叔丁基过氧化己烷/偶氮二甲酰胺(双二五/AC)和过氧化苯甲酰(BPO)/AK 3种硫化发泡体系及助交联剂TAIC对硅橡胶泡沫材料力学性能和压缩应力松弛性能以及泡孔结构的影响。结果表明,DCP/H硫化发泡体系的力学性能和应力松弛性能优于双二五/AC和BPO/AK,添加适量助交联剂TAIC有助于进一步降低硅橡胶泡沫材料的应力松弛性能。扫描电镜(SEM)观察发现,DCP/H硫化发泡体系对应的硅橡胶发泡材料泡孔较小且分布均匀,当加入适量的助交联剂TAIC后,硅橡胶泡沫材料的泡孔更加细小均匀。     

不同种类硫化剂对氢化丁腈橡胶性能的影响

研究了硫化剂过氧化二异丙苯（DCP）、双叔丁基过氧化异丙基苯（BIPB）和2,5-二甲基-2,5-双(叔丁基过氧化)己烷（DHBP）对氢化丁腈橡胶性能的影响。结果表明,在分解出相同自由基数量的情况下,使用DCP胶料的门尼黏度增值最小,焦烧时间最短、硫化速率最快,硫化胶的拉伸强度最小,耐老化性能最好;使用DHBP胶料的焦烧时间最长、硫化速率最慢,硫化胶的硬度和定伸应力都更低,拉伸强度和扯断伸长率均为最高,压缩永久变形和耐油性能都是最差;使用BIPB橡胶的焦烧时间、硫化速率和拉伸强度均居于前二者中间,压缩永久变形最小,耐老化性能最差,门尼黏度增值与使用DHBP相当,其他物理机械性能和耐油性能与使用DCP相当。     

硫化剂对硅橡胶性能的影响

考察硫化剂TX-29、双2,5、双2,4和DCP对硅橡胶硫化特性和物理性能的影响。试验结果表明:采用硫化剂DCP的硅橡胶的综合物理性能最佳;可根据生产工艺、成本和性能要求,选用不同的硫化剂来实现产品性能目标。     

MVQ/ACM并用胶料硫化特性的研究

研究硫化剂DCP、硫化剂双2 5和两者并用硫化体系对甲基乙烯基硅橡胶(MVQ)/ACM并用胶料硫化特性的影响。结果表明,硫化剂DCP和硫化剂双2 5硫化的胶料最大转矩(MH)均随硫化剂用量的增大先增大后减小,硫化效果均较好。采用硫化剂双2 5/硫化剂DCP并用体系硫化的胶料能获得更快的硫化速度,且MH较大;当硫化剂双25/硫化剂DCP并用比为0.15/0.5时,MH高达20 dN.m,比硫化剂双25或硫化剂DCP单用时提高约30%。进行二段硫化有利于提高MVQ/ACM并用胶的物理性能,二段硫化温度为200℃时,硫化时间以3~4h为宜。     

硫化剂种类对阻燃硅橡胶性能的影响

研究了双叔丁基过氧化异丙基苯(BIPB)、过氧化二异丙苯(DCP)、过氧化苯甲酰(BP)、2,4-二氯过氧化苯甲酰(DCBP)四种硫化剂对阻燃硅橡胶力学性能和阻燃性能的影响.结果表明:随硫化剂用量的增加,硅橡胶的扯断伸长率降低,硬度提高,拉伸强度和氧指数变化很小;二次硫化后,硅橡胶的硬度提高,扯断伸长率降低,采用BP的硅橡胶的拉伸强度降低,采用其它三种硫化剂的硅橡胶的拉伸强度则提高;阻燃性均提高;硫化剂种类对硅橡胶的耐热性没有明显影响.     

硫化剂对三元乙丙橡胶/乙烯辛烯共聚物性能的影响

研究了2,5-二甲基-2,5-双(叔丁基过氧基)己烷(DBPH)和过氧化二异丙苯(DCP)对三元乙丙橡胶(EPDM)/乙烯辛烯共聚物(POE)性能的影响。结果表明,在硫化剂用量相同的条件下,使用DCP硫化的EPDM/POE共混物正硫化时间和邵尔A硬度均比DBPH硫化胶的小,DCP硫化胶的拉伸强度和拉断伸长率均优于DBPH硫化胶,但DBPH硫化胶的热空气老化性能优于DCP硫化胶。正交试验结果表明,理想的硫化体系是5份DBPH、1.5份三烯丙基异氰脲酸酯(TAIC)和和0.2份硫黄(S)。     

过氧化物体系交联混炼型聚氨酯橡胶的研究

以自制聚己二酸二乙二醇聚酯和4,4′-二苯基甲烷二异氰酸酯(MDI)为主要原材料合成了聚氨酯生胶,并添加白炭黑补强剂和4种不同过氧化物硫化剂制备了混炼型聚氨酯(MPU)橡胶。研究了过氧化二异丙苯(DCP)、双叔丁基过氧异丙基苯(BIPB)、1,1-双叔丁基过氧化-3,3,5-三甲基环已烷(TMCH)和2,5-二叔丁基过氧化-2,5-二甲基已烷(DBPMH)4种硫化剂对MPU橡胶力学性能的影响,探讨了白炭黑用量、DCP用量以及热空气老化对MPU力学性能的影响。结果表明,DCP-PU的硬度和TMCH-PU的拉伸强度最高,TMCH-PU和DBPMH-PU的拉断伸长率达到750%以上。随着DCP用量的增大,MPU橡胶硬度和定伸应力提高,拉断伸长率下降;当DCP用量达到1.6份时,拉伸强度达到23.4 MPa。白炭黑用量越大,MPU橡胶综合力学性能越好。     

硫化剂配比对硅橡胶泡沫材料发泡效果的影响

以甲基乙烯基硅橡胶为生胶,白炭黑为填料制得混炼胶,以过氧化二苯甲酰(BPO)和过氧化二异丙苯(DCP)为硫化剂,采用二次硫化工艺制备了硅橡胶泡沫材料。考察了硫化剂BPO与DCP的配比对硅橡胶泡沫材料性能及发泡效果的影响。结果表明,相比一次硫化工艺,二次硫化工艺能有效提高硅橡胶泡沫的力学性能并达到较好的发泡效果。当BPO与DCP的质量比为0.8∶4时,制得的硅橡胶泡沫材料泡孔相对较大,且泡孔分布较均匀、泡孔壁较薄、孔隙度高,发泡效果最佳。     

硅橡胶/顺丁橡胶/乙丙橡胶共混材料的研究

针对硅橡胶具有较高耐热性．但力学性能差；三元乙丙橡胶（EPDM）力学性能较好，但互粘性较差；顺丁橡胶（BR）弹性好．但加工性能堇的特点，提出了将硅橡胶、三元乙丙橡胶与顺丁橡胶共混的方法，制成共混材料；再通过测定样品的性能，确定共混的最佳配比。结果表明：BR与EPDM、硅橡胶相客性较好，可达到共硫化；硅橡胶／BR／EPDM质量比为20／30／50时，共混物的物理机械性能和老化性能较好；用过氧化二异丙苯（DCP）／硫磺作硫化剂要好于用硫磺、过氧化二苯甲酰（BPO）和硫磺／BPO硫化剂。试样的耐热老化性能、邵尔A型硬度和扯断伸长率较好，其中样品的综合性能具备了硅橡胶、顺丁橡胶和三元乙丙橡胶的优点。     

Systematic investigation on the effect of crosslinking agent type and dosage on the performance of TPU/MVQ based thermoplastic vulcanizates

Dynamic vulcanized thermoplastic polyurethane (TPU)/methyl vinyl silicone rubber (MVQ) thermoplastic vulcanizates (TPVs) were prepared in torque rheometer. The influence of the type and amount of peroxide crosslinking agent on the mechanical properties, thermal stability, micromorphology and melt flowability was systematically investigated. The results showed that the mechanical properties of the TPVs vulcanized by 2,5-dimethyl-2,5-di (tert-butyl peroxy) hexane (DBPH) first increased and then decreased with increasing the peroxide amount, while for dicumyl peroxide (DCP) vulcanizing system the mechanical properties slowly increased. Besides, the comprehensive mechanical properties vulcanized by DBPH were better than those of DCP group. The results of the thermogravimetric analysis showed that the TPVs vulcanized by DBPH had better heat stability, corresponding to the excellent thermo-oxidative aging performance and the 38% increase in tensile strength after aging. In addition, the MVQ rubber particles showed better dispersing performance for DBPH vulcanizing system. The melt flow rate of the TPVs showed a linear relationship with increasing DBPH dosage and became worse after the amount of crosslinking agent exceeded 1.5 phr. By comprehensive comparison, the TPVs have better performance when use peroxide DBPH as the crosslinking agent and the dosage is 1.5 phr.     

Mechanical properties and antibacterial activity of peroxide‐cured silicone rubber foams

Silicone rubber (SR) foams were prepared by the peroxide curing of a silicone compound with 2,4‐dichlorobenzoyl peroxide (DCBP), di‐t‐butyl peroxide (DTBP), or 2,5‐dimethyl‐2,5‐di(t‐butylperoxy) hexane (DBPH) in the presence of 2,2′‐azobisisobutyronitrile (AIBN) as a blowing agent. The cells were formed in the foam as a result of nitrogen produced by the decomposition of AIBN during the foaming process. The cell size, hardness, and tensile properties of the SR foams were examined as a function of the peroxide concentration. When the peroxide concentration increased, the hardness and tensile strength of the SR foams increased, whereas the cell size and elongation at break decreased. The antibacterial activity of the prepared foams was also evaluated via their effects on Staphylococcus aureus and Escherichia coli. The peroxide‐cured SR foams had antibacterial activity because a toxic residue was generated by the peroxide decomposition. The foam prepared by the AIBN/DCBP system showed more antibacterial activity than the AIBN/DBPH and AIBN/DTBP ones. However, after postcuring at 250°C for 2 h, the antibacterial activity of the SR foams significantly decreased. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

过氧化物硫化聚醚型聚氨酯混炼橡胶力学性能的研究

研究了过氧化物过氧化二异丙苯（DCP）、双叔丁基过氧化异丙基苯（BIPB）和补强剂（炭黑或白炭黑）对聚醚型聚氨酯混炼橡胶力学性能的影响,讨论了DCP和补强剂用量变化及不同硫化条件对混炼橡胶力学性能的影响。结果表明,DCP硫化混炼胶定伸应力高,永久变形小;BIPB硫化混炼胶硬度和强度高;当DCP用量在1．6份时,混炼胶拉伸强度和撕裂强度最高;提高补强剂用量,混炼胶硬度和定伸应力增加,拉伸强度变化不明显,但永久变形变大。     

硫化体系对EPDM硫化胶力学性能的影响

考察了4,4′-二硫代二吗啉（DTDM）,N,N′-间苯撑双马来酰亚胺（HVA-2）,甲基丙烯酸镁与硫黄和过氧化二异丙苯（DCP）复合硫化体系对三元乙丙橡胶力学性能的影响。结果表明,与纯硫黄硫化胶相比,DTDM/HVA-2/S复合硫化体系的EPDM硫化胶拉断伸长率及压缩永久变形均较小,而拉伸强度、定伸应力和硬度均较大,耐老化性能较好。甲基丙烯酸盐可明显提高硫黄、过氧化物硫化EPDM硫化胶的交联密度、拉伸强度、定伸应力和拉断伸长率。在甲基丙烯酸镁/炭黑/EPDM胶料中添加等量S i69改性白炭黑和石蜡油后,硫化胶各项力学性能都有明显提高,定伸应力和硬度保持较低水平,耐热空气老化性能有所改善。     

氢化丁腈橡胶配方优化的回归试验设计

利用回归分析法研究甲基丙烯酸锌(ZDMA)和过氧化二异丙苯(DCP)用量对氢化丁腈橡胶(HNBR)性能的影响。结果表明:随着DCP用量增大,胶料的t90缩短,Fmax、回弹值和DIN磨耗量增大,拉伸强度、撕裂强度和压缩永久变形减小;随着ZDMA用量增大,胶料的t90缩短,Fmax、硬度、拉伸强度、撕裂强度、DIN磨耗量和压缩永久变形增大,回弹值减小;回归分析法可用于建立HNBR胶料各项性能与配方各组分用量之间的方程式,从而对配方进行优化。     

Peroxide cured natural rubber/fluoroelastomer/high‐density polyethylene via dynamic vulcanization

In this work, blends of fluoroelastomer (FKM), natural rubber (NR) along with high‐density polyethylene (HDPE) by dynamic vulcanization using peroxide (DBPH, DCP) as a curing agent were prepared. HDPE was melt‐mixed with NR and FKM at different compositions (HDPE/FKM/NR i.e. 30/60/10, 30/55/15, 30/50/20, and 30/35/35%wt) using an internal mixer at 150°C and 50 rpm rotor speed. The mechanical properties and oil swelling resistances of these blends were analyzed according to ISO 37 (Type 1) and ASTM D471, respectively. The results suggest that DBPH works better as a curing agent for the dynamic vulcanization system than DCP. The optimum mechanical properties and oil resistance were revealed in 30/50/20 and 30/60/10 HDPE/FKM/NR, being dynamic vulcanized with DBPH, respectively. In addition, was found that a dispersed HDPE phase shows the percent crystallinity in the range of 53% to 55% upon increasing the NR content. The SEM micrographs reveal the NR phase is well dispersed in FKM as small particles. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers .     

乙烯基三乙氧基硅烷用量对液体硅橡胶性能的影响

以乙烯基硅油为原料,含乙烯基三乙氧基硅烷（A-151）就地处理过的气相法白炭黑为填料,制得高硬度、高强度加成型液体硅橡胶。研究了A-151的用量对加成型液体硅橡胶性能的影响。结果表明,A-151的用量能显著影响硅橡胶的硫化特性,随着A-151用量的增加,硅橡胶胶料的焦烧时间逐渐缩短,而正硫化时间则逐渐延长;硅橡胶的拉伸强度、撕裂强度、电气强度等先增后降,拉断伸长率降低、邵尔A硬度上升,胶料的起始黏度和黏度增长率上升,对硅橡胶的体积电阻率影响不大。当A-151的用量为1份时,硅橡胶的拉伸强度达最大值（8．8MPa）、撕裂强度为22．2kN／m、邵尔A硬度为50度、拉断伸长率为370％、电气强度为22．5kV／mm、体积电阻率为13．5×10^5Ω·cm,对硅橡胶的黏度和黏度增长率影响较小。