正交设计法优化三元乙丙橡胶/丙烯酸酯橡胶并用胶的硫化体系

采用正交设计法研究硫化剂DCP/TCY并用硫化体系中硫化剂和促进剂用量对三元乙丙橡胶(EPDM)/丙烯酸酯橡胶(ACM)并用胶物理性能的影响。结果表明:硫黄和氧化锌用量对EPDM/ACM并用胶拉伸强度有显著影响,硫化剂DCP用量对拉伸强度有一定影响;硫化剂DCP、TCY和硫黄用量均对撕裂强度有显著影响,氧化锌用量对撕裂强度有一定影响;硫化剂DCP、促进剂DM和氧化锌用量对并用胶的耐热老化性能有影响;在正交设计试验范围内,并用胶综合性能较好的优化配方为:硫化剂DCP 3,硫化剂TCY 2,硫黄0.3,促进剂DM 0.25,氧化锌5。     

共混比对ACM／FKM共混胶性能的影响

采用硫化剂TCY为共硫化剂,研究了共混比对丙烯酸酯橡胶／氟橡胶共混胶的硫化特性、力学性能、耐热老化性能和耐油性能的影响。结果表明：TCY可以同时硫化两种橡胶;ACM／FKM共混比为20／80时．硫化胶具有较好综合力学性能和耐热老化性能;随着ACM用量的增加,硫化胶耐油性能逐渐下降。     

TCY/TRA复合硫化体系对ACM/ECO共混胶性能的影响

分别采用TCY/TRA和TCY/NA-22两种硫化体系硫化 ACM/ECO共混胶.研究了不同硫化体系、TCY用量和TRA用量对ACM/ECO共混胶的硫化特性,力学性能、耐热老化性能、耐油性能和高温压缩xxx永久变形性能的影响.结果表明,TCY/TRA硫化体系能使ACM/ECO共混胶实现共硫化;其用量为1.5份/1.5份...     

复合硫化体系对ACM/NBR共混胶性能的影响

分别采用TCY/硫黄、3#硫化剂/硫黄/促进剂、皂/硫黄/促进剂3种复合硫化体系硫化ACM/NBR共混胶。研究不同复合硫化体系、TCY用量和硫黄用量对ACM/NBR共混胶硫化特性、力学性能、耐热老化性能、耐油性能和压缩永久变形性能的影响,结果表明,TCY/硫黄复合硫化体系硫化的ACM/NBR共混胶的综合性能优于3#硫化剂/硫黄/促进剂和皂/硫黄/促进剂复合硫化体系,当TCY/硫黄的用量为1.5/0.3份时,ACM/NBR共混胶具有良好的综合物理机械性能。     

无ZnO硫磺/TCY硫化体系对ACM/NBR共混胶性能的影响

研究了无ZnO情况下TCY/S用量对丙烯酸酯橡胶(ACM)/丁腈橡胶(NBR)共混胶的硫化特性、两相交联密度、老化前后物理机械性能的影响,并与ACM、NBR硫化胶做了性能对比。结果表明,随着TCY/S用量增大:ACM/NBR硫化速度逐渐加快,整体硫化程度增大;ACM相交联密度先增大后不变,NBR相交联密度增大,共混胶中各相交联密度与各自纯胶交联密度大致相同;硫化胶硬度和模量上升,扯断伸长率下降,拉伸强度先上升后下降,TCY/S用量1/0.75时拉伸强度达到最大值;热油和热空气老化之后拉伸强度较老化前下降,且下降幅度与TCY/S用量成正比,热油老化之后的体积质量变化率下降;ACM/NBR共混胶的力学性能好于对应的ACM、NBR硫化胶。     

硫化体系对CR／SBR共混胶性能的影响

探讨了给硫体和TCY／给硫体2种不同硫化体系对CR／SBR共混胶硫化特性、硫化橡胶力学性能和耐热老化性能的影响。结果表明：含DTDM的共混胶焦烧时间较长。正硫化时间较短,硫化特性较好。采用TCY／给硫体复合硫化体系且随着TCY用量的增加,CR／SBR硫化橡胶拉伸强度先增大后减小,TCY用量为1份拉伸强度达到最大值（23．0MPa）。2种不同硫化体系的硫化橡胶耐热老化性能都较好,老化后拉伸强度保持率在100％左右,拉断伸长率保持率也在70％左右。     

EPDM/NR共混橡胶的性能研究

采用硫黄硫化体系和过氧化物(硫化剂DCP)硫化体系对EPDM/NR并用胶实施复合交联,考察了不同共混比EPDM/NR共混胶的硫化特性、硫化胶的物理机械性能、耐水性及耐溶剂性能。结果表明:复合交联后,胶料的硫化特性、物理机械性能均有所提高;EPDM母炼胶中DCP的用量要高于NR;胶料共混比为80/20(EPDM/NR),其耐水性和耐溶剂性能达到最佳。     

ACM/EPDM并用胶的制备及性能

以丙烯酸酯橡胶(ACM)和三元乙丙橡胶(EPDM)为主要原料制备共混材料。通过ACM/EPDM的质量比、白炭黑用量和硫化工艺条件的研究发现,用白炭黑作补强剂的硫化胶性能优于用炭黑作补强剂的硫化胶;当EPDM/ACM为25/75,硫化条件为160℃×10 MPa×30 min时,该共混材料具有良好的力学性能、耐磨、耐热和耐油性,ACM/EPDM并用胶的性能优于ACM或EPDM的性能。     

硫化剂TCY/硫黄并用硫化体系对ACM性能的影响

研究硫化剂TCY/硫黄并用硫化体系对丙烯酸酯橡胶(ACM)性能的影响.结果表明,硫化剂TCY和硫黄用量对ACM硫化胶的耐油性能影响不大;当硫化剂TCY用量为1.5份、硫黄用量为0.3份时,ACM胶料的硫化速度较快,硫化胶各项性能较好,特别是耐热空气老化性能优异.     

EPDM/CM耐高热输送带覆盖胶配方探讨

以三元乙丙胶（EPDM）与氯化聚乙烯（CM）并用为主体材料，根据耐高热输送带覆盖胶性能要求，采用机械共混、化学交联工艺制得EPDM／CM耐高热胶带覆盖胶，初步探讨了EPDM／CM共混比例、硫化体系、补强填充剂对覆盖胶性能的影响。实验结果表明，采用EPDM-K512／EPDM-4050／CM-352L的共混比为35／65／30时，既能改善胶料工艺性能，又提高了其拉伸强度、硬度；采用过氧化二异丙苯（DCP）／硫磺（S）／三烯丙基异氰脲酸酯（TAIC）的比例为5．5／0．3／2时，有良好的耐热老化性能和拉伸强度；此外采用中超炭黑（ISAF）／通用炭黑／白炭黑的配比为45／10／5时补强体系的性能最好。     

Dynamic vulcanization of recycled milk pouches (LDPE–LLDPE) and EPDM blends using dicumyl peroxide

The viability of thermomechanical recycling of post‐consumer milk pouches (blend of low‐density polyethylene (LDPE) and linear low‐density polyethylene (LLDPE)) and its scope for suitable engineering applications were investigated. The effects of blending with ethylene‐propylene‐diene monomer (EPDM) rubber and subsequent curing using dicumyl peroxide (DCP) on the macromolecular structure and properties of recycled polyethylene (PE) blends were studied. The crosslinking efficiency of recycled PE/EPDM blends and possible thermooxidative degradation of recycled polymer upon peroxide curing was assessed using torque and gel content measurements along with infrared spectroscopic analysis. Both the torque and gel content of the blends varied with DCP crosslinking reactions and also were affected by oxidative degradation. In view of the electrical application area of this recycled blend material, the dielectric breakdown strength and volume resistivity were measured. The mechanical performance and thermal stability of recycled PE/EPDM blends improved with progressive crosslinking by DCP but deteriorated somewhat at higher DCP dose. Scanning electron microscopy showed good interface bonding between recycled polymer and dispersed EPDM phase in the cured blends compared to the non‐cured blends. Copyright © 2007 Society of Chemical Industry     

Rheological properties and crystalline structure of the dynamically cured EPDM and PP/HDPE ternary blends

The rheological properties and crystalline structure of the polyolefin ternary blends of EPDM/polypropylene/high density polyethylene were studied. Blends were prepared in a laboratory internal mixer by two different methods. In blend–cure process, blending and curing were performed simultaneously and EPDM was cured by dicumyl peroxide (DCP) in the presence of PP/HDPE under shear. The cure–blend was to cure EPDM alone first under shear (dynamic curing) and then mix the cured EPDM with PP and HDPE. The effect of DCP concentration, intensity of the shear mixing, and the rubber/plastic composition were studied using capillary rheometer and X-ray diffractometer. The PP-rich ternary blends showed the effect of the mechanooxidative degradation of PP by shear and peroxide. The melt viscosity increased with increasing DCP concentration in blends of EPDM-rich compositions. X-ray diffraction studies revealed that the inclusion of 25 wt % of linear EPDM in the PP/HDPE mixture for the PP-rich ternary blends changed the crystal structure of polypropylene component in the ternary blends. However, the dynamic curing did not alter the crystal structure of PP or HDPE in the blends.     

动态硫化PP／HDPE／EPDM三元共混物的流变性能

本文采用不同的硫化剂，不同的硫化时间，对动态硫化的ＰＰ／ＨＤＰＥ／ＥＰＤＭ三元共混物的流变性能进行了研究。结果表明：１共混体系为假塑体，表现出切力变稀现象；２在低剪切应力下，以Ｍ为硫化剂的粘度与纯机械共混体系的粘度有很大差值，此差值随剪切应力的提高迅速减少；３以ＤＣＰ为硫化剂，体系的粘度低于纯机械共混体系的粘度。     

HNBR/EPDM共混物结构与性能研究

分别采用过氧化物和硫给予体作交联剂,考察了不同共混比对氢化丁腈橡胶（ＨＮＢＲ）／ＥＰＤＭ共混物性能的影响,并能力ＤＳＣ和ＴＥＭ分析了共混物的相容性,对两胶的共硫化也作了初步探讨。结果表明,两种硫化体系硫化的共混胶扯断伸长率保持率均在６０％以上,都具有优异的耐热氧老化性能。随ＨＮＢＲ用量增大,共混物的定伸应力、拉伸强度和撕裂强度均提高,磨耗明显降低。ＨＮＢＲ和ＥＰＤＭ为不相容体系,但硫化仪曲线显示二     

助交联剂PDM和硫黄用量对CM/EPDM并用胶性能的影响

试验研究在过氧化物硫化体系下助交联剂N,N'-间亚苯基双马来酰亚胺(PDM)和硫黄用量对氯化聚乙烯橡胶(CM)/EPDM并用胶性能的影响.结果表明:在硫化剂DCP/助交联剂PDM硫化体系下,当硫化剂DCP用量为3份、助交联剂PDM用量为1.5～2份时,CM/EPDM并用胶的综合性能较好;在硫化剂DCP/硫黄硫化体系下,...     

EPDM/NR并用胶的复合交联

采用硫黄硫化体系和过氧化物（硫化剂DCP）硫化体系对EPDM／NR并用胶实施复合交联，研究并用比和复合交联体系对胶料的硫化特性、物理性能和耐热老化性能的影响。结果表明，在大部分并用比下，复合交联可以改善胶料的硫化特性；在硫化剂DCP和助交联剂TAIC的用量均为2份、EPDM／NR／ENR并用比为30／68．5／1．5时，并用胶的物理性能优良；以NR为主的并用胶在复合交联时硫化剂DCP和助交联剂TAIC的用量宜取1～2份。     

Tensile properties and morphology of the dynamically cured EPDM and PP/HDPE ternary blends

The tensile properties and morphology of the polyolefin ternary blends of ethylenepropylene–diene terpolymer (EPDM), polypropylene and high density polyethylene were studied. Blends were prepared in a laboratory internal mixer where EPDM was cured in the presence of PP and HDPE under shear with dicumyl peroxide (DCP). For comparison, blends were also prepared from EPDM which was dynamically cured alone and blended with PP and HDPE later (cure–blend). The effect of DCP concentration, intensity of the shear mixing, and rubber/plastics composition was studied. The tensile strength and modulus increased with increasing DCP concentration in the blends of EPDM-rich compositions but decreased with increasing DCP concentration in blends of PP-rich compositions. In the morphological analysis by scanning electron microscopy (SEM), the small amount of EPDM acted as a compatibilizer to HDPE and PP. It was also revealed that the dynamic curing process could reduce the domain size of the crosslinked EPDM phase. When the EPDM forms the matrix, the phase separation effect becomes dominant between the EPDM matrix and PP or HDPE domain due to the crosslinking in the matrix.