氯醚橡胶/超细全硫化粉末硅橡胶共混物的结构与性能

采用熔融共混工艺制备氯醚橡胶(ECO)/超细全硫化粉末硅橡胶(UFPSiR)共混物,并对共混物的相态结构与性能进行研究.结果表明,UFPSiR在ECO中的分散性较差,粒径为微米级;UFPsiR与ECO的相容性不好,ECO/UFPSiR共混物的物理性能与ECO/硅橡胶共混物差别不大,但耐热氧老化性能较好,加入少量UFPsiR能够显著减小共混物的压缩永久变形.     

Toughening of polypropylene by combined rubber system of ultrafine full-vulcanized powdered rubber and SBS

A combined rubber system of ultrafine full-vulcanized powdered rubber (UFPR) and SBS was used for polypropylene toughening. The PP toughened with the combined rubber system shows not only higher impact strength as compared to each rubber component used alone but also good stiffness and heat resistance. Crystallization study shows that the UFPR is more efficient in promoting the crystallization of PP than SBS, leading to a higher crystallinity and an enhancement of stiffness and heat resistance of PP. The combined rubber system containing UFPR and a small amount of SBS still possesses a good nucleating ability. Transmission electron microscopy results indicate that the combined rubber system mostly forms an encapsulation structure of UFPR particles encapsulated by SBS phase. This morphology was also confirmed by scanning electron microscopy results through observing the fracture surfaces of toughened samples. A small amount of SBS was found to be helpful for a better dispersion of UFPR in PP matrix. The causes for the encapsulation morphology and the synergistic toughening effect were discussed. A tentative explanation was given by comparison of the solubility parameter of each component in the toughened samples.     

超细全硫化粉末丁腈橡胶在聚氯乙烯改性塑料中的应用

介绍了超细全硫化粉末丁腈橡胶及其在硬质聚氯乙烯和软质聚氯乙烯两种材料共混增韧改性中的应用进展。与普通粉末丁腈橡胶P83的增韧性相比,采用少量的超细全硫化粉末橡胶即能够在保持较高强度和耐热温度的基础上,大幅度提高PVC改性材料的韧性。     

NR／SBR并用胶性能研究

试验研究为然橡胶/丁苯橡胶NR／SBR并用比及填充体系对胶料综合性能的影响。实验表明,当NR／SBR为70／30,炭黑N330,补强剂Le为30／10时,胶料具有较优异的加工性能、物理机械性能和动态性能,即达到各种性能之间的平衡。     

抗裂口树脂AD-1600对NR/SBR并用胶性能的影响

研究了补强树脂种类及抗裂口树脂AD-1600用量对天然橡胶/丁苯橡胶（NR/SBR）并用胶性能的影响。结果表明,抗裂口树脂AD-1600、补强树脂OD-60均可提高NR/SBR硫化胶的拉伸强度、撕裂强度及耐磨耗性等性能;随AD-1600用量增加,拉伸强度和撕裂强度先增大后减小,DIN磨耗体积先减小后增大,呈单峰型变化规律,但各项性能达到最佳值时AD-1600用量不一致。     

Continuous ultrasonic devulcanization of NR/SBR blends

The ultrasonic devulcanization of sulfur‐cured natural rubber (NR)/styrene–butadiene rubber (SBR) blends was studied with the goal of understanding the devulcanization of rubber vulcanizates in which two networks of different natures were present. Also, similarities and differences in the devulcanization behaviors of NR, SBR, and their blends were found. During the devulcanization of cured NR/SBR blends, we observed that, as for NR, the ultrasonic power consumption for 75/25 and 50/50 (w/w) NR/SBR blends passed through a maximum at 7.5 μm. For SBR and 25/75 (w/w) NR/SBR blends, the power consumption increased with increasing ultrasonic amplitude. The higher power consumption led to a higher degree of devulcanization. The crosslink densities of the devulcanized 25/75, 50/50, and 75/25 (w/w) NR/SBR blends were lower than those of the devulcanized NR and SBR, possibly because of the reduced degree of unsaturation. The tensile properties of the revulcanized blends were lower than those of the virgin vulcanized blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 160–168, 2002     

超细全硫化粉末丁腈橡胶/二元共聚氯醚橡胶共混物的结构与性能

采用熔融共混工艺制备了超细全硫化粉末丁腈橡胶(UFPNBR)/二元共聚氯醚橡胶(ECO)共混物,研究了共混物的相态结构、动态力学性能、物理机械性能及老化性能,并与丁腈橡胶(NBR)/ECO共混物进行了对比.透射电镜观察表明,在UFPNBR/ECO体系中,UFPNBR为分散相,ECO为连续相;而在NBR/ECO体系中,ECO为分散相,NBR为连续相.动态力学性能分析结果显示在共混质量比不超过50/50时,UFPNBR/ECO共混物只存在1个玻璃化转变温度;当共混质量比超过50/50时分散相尺寸较大,出现2个玻璃化转变温度,而NBR/ECO始终存在2个玻璃化转变温度.加入适量的UFPNBR(不超过50份,质量)能降低UFPNBR/ECO共混物的压缩永久变形.与NBR/ECO共混物相比,UFPNBR/ECO共混物的脆性温度较低,耐老化性能更好,但物理机械性能稍差.     

Thermal effects of heat-resistant rubber blends. I. Joule heating effects in carbon black-loaded NR/SBR blends

A heat-resistant rubber blend of natural rubber NR and styrene butadiene rubber (SBR-1502) was prepared according to the standard techniques. The rubber blend was loaded with different concentrations of LAMP black and general purpose furnace (GPF) black for obtaining conductive rubber composites. The obtained vulcanizates were subjected to electrical conductivity measurements over a wide range of temperature and electric field. It was found that all samples showed negative values of temperature coefficient of conductivity (TCC). The temperature developed inside the samples by the Joule heating effect was recorded as a function of time (T–t) at different values of the initial applied DC-electric power. The T–t dependence was found to obey an exponentially growing function with a time constant (τ), which was found to be dependent on the concentrations as well as the type of carbon black and the value of the initial applied power. The current–voltage characteristics of the samples showed a negative resistance behavior after a characteristic voltage (V^*). It was noticed that V^* decreases as the carbon black concentration increases.     

超细粉末羧基丁苯橡胶增韧PC/ABS性能研究

研究了超细粉末羧基丁笨橡胶(UFPR)对聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)合金机械性能的影响.结果表明:随着UFPR用量的增加,PC/ABS合金的拉伸强度、弯曲强度有所降低,断裂伸长率明显提高,悬臂梁缺口冲击强度先升高后明显降低.当UFPR用量为0.5～2.0 phr时,PC/A BS合金悬臂...     

NR/SBR乒乓球拍胶皮的制备研究

以天然橡胶（NR）与丁苯橡胶（SBR）并用制造乒乓球拍胶皮。研究了并用比、促进剂、碳酸钙用量对NR/SBR并用胶性能的影响。研究结果表明,NR/SBR质量比为80/20,促进剂二硫化二苯并噻唑（DM）、2-硫醇基苯并噻唑（M）、二苯胍（D）各1.25、1.25、2.5份,共用量5份,并用胶具有最大拉伸强度和扯断伸长率;碳酸钙为260份,胶皮无喷霜。     

P(SBR/NR/HAF)并用胶的性能

在SBR胶乳／NR胶乳共混的基础上，采用凝聚共沉法制备高耐磨炭黑（HAF）填充型粉末丁苯橡胶／天然橡胶并用胶[P(SBR/NR/HAF)]。研究了SBR／NR并用比、制备工艺等对P（SBR／NR／HAF）并用胶的混沌流变性能和物理机械性能的影响，并与块状SBR／NR／HAF并用胶进行了比较。研究表明，与SBR／NR／HAF相比，P（SBR／NR／HAF）的表观剪切粘度在SBR用量小于50份时对混炼时间的依赖性较低，而在SBR用量大于50份后对混炼时间具有更高的依赖性；P（SBR／NR／HAF)硫化胶 拉伸强度在整个并用范围内对SBR／NR并和比不敏感；采用胶乳预混合的工艺制备的P（SBR／NR／HAF）具有较好的物理机械性能。     

超细碳酸钙填充粉末丁苯橡胶的制备

将高分子电解质包覆剂和超细碳酸钙加入丁苯胶乳中,通过共凝聚法制得粉末丁苯橡胶（PSBR）。实验结果表明,PSBR 粒径不大于0.9mm,具有良好的力学性能。PSBR的粒径主要由包覆剂的用量决定,超细碳酸钙对橡胶粒子有隔离作用。     

NR/SBR并用橡胶基磁敏橡胶的制备及性能的研究

通过湿法预处理,用偶联剂KH-570对羰基铁粉进行表面改性,制备了综合性能较好的并用橡胶基实用型磁敏橡胶,研究了羰基铁粉含量对天然橡胶/丁苯橡胶(NR/SBR)并用橡胶基磁敏橡胶性能的影响;同时利用扫描电镜研究了改性羰基铁粉表面和磁敏橡胶复合材料断面的微观结构。结果表明,通过偶联剂改性的羰基铁粉其晶体结构未发生变化,且表面有一层致密的包覆层;以NR/SBR并用橡胶为基体的磁敏橡胶,当羰基铁粉用量为300份时,可表现出较好的机械性能和磁流变效应。     

纳米SiO2改性NR/SBR共混胶的结构与性能研究

研究了纳米SiO2加入方式及用量对NR/SBR共混胶的正硫化时间、力学性能的影响,并研究了纳米SiO2改性前后共混胶的耐热分解性能、耐热空气老化性能及微观形态结构.结果表明:纳米SiO2的加入对共混胶的正硫化时间、力学性能及耐热稳定性能有较大影响;当纳米SiO2加入量为7％(质量分数)并采用NR/SBR共混均匀后先加入纳米SiO2,再加入小料、硫磺的方式制备NR/SBR共混胶时,纳米SiO2通过使NR/SBR共混胶的分散相细化并使共混胶的整体交联密度提高,有效地提高了NR/SBR共混胶的综合力学性能和耐热稳定性能,达到了对NR/SBR共混胶良好的补强改性效果.     

纳米碳酸钙在NR/BR/SBR并用胶中的应用研究

采用带有酚醛基的反应性有机改性剂对纳米碳酸钙CCR进行改性制得M-CCR,并制备了NR/BR/SBR/CCR和NR/BR/SBR/M-CCR复合材料,研究了两种复合材料的微观形态以及力学性能和加工性能。结果表明,M-CCR在并用胶中的分散性优于CCR,对并用胶力学性能的提高更显著;两种填料都能改善并用胶的加工性能,并且不影响并用胶的抗湿滑性和滚动阻力。     

双马来酰亚胺衍生物对炭黑填充NR/ SBR并用胶硫化特性的影响

测定了含双马来酰亚胺衍生物（Ｐｅｒｋａｌｉｎｋ９００）的充炭黑ＮＲ／ＳＢＲ并用胶质量比为８０／２０时,于１４５℃×６０ｍｉｎ,１８０℃×３０ｍｉｎ的硫化曲线,考察了Ｐｅｒｋａｌｉｎｋ９００用量对混炼胶硫化特性的影响。结果表明,在试验范围内,Ｐｅｒｋａｌｉｎｋ９００的加入不改变胶料的焦烧和正硫化,但能有效地改善胶料的流动特性;可提高橡胶的抗撕裂性能,且不影响其他物理机械性能;对胶料的硫化返原性具有显著的改进效果。Ｐｅｒｋａｌｉｎｋ９００加入量以１．０份为宜。     

超细全硫化粉末丁苯橡胶改性沥青的性能及相容剂的影响

采用低温高剪切改性工艺,用超细全硫化粉末丁笨橡胶(UFPSBR)对沥青进行改性,研究了UFPSBR的加入量和相容剂对沥青基本性能和动态力学性能的影响以及改性沥青的微现形貌.结果表明,随着UFPSBR掺入量的增加,改性沥青的软化点升高,25℃针入度减小,5℃延度提高,弹性模量和损耗模量都明显增大.相容剂的加入增强了UFP...     

动态硫化通用聚苯乙烯/粉末丁苯橡胶共混物的性能

采用双螺杆动态硫化工艺,用粉末丁苯橡胶(PSBR)改性通用聚苯乙烯(GPS)制备GPS/PSBR共混物,考察了二者的质量比、软化剂用量、增强剂种类和加工工艺对共混物性能的影响,并对共混物的性能与高抗冲型聚苯乙烯(HIPS)进行了对比.结果表明,当GPS与PSBR的质量比为80∶20时,使用软化剂可提高共混物的加工流动性;纳米高岭土对共混物有较明显的增强作用;用动态硫化工艺制得共混物的性能与HIPS相当,其耐老化性能优于非动态硫化工艺制得的共混物.     

Effect of fillers on morphological properties in NR/SBR blends for OTR tyres

Abstract

The blends of styrene butadiene rubber (SBR) and natural rubber (NR) are prepared using a two-roll mixing mill in the presence of different types of carbon blacks as reinforcing filler. The effects of fillers on cure characteristics and thermal, dynamic–mechanical, morphological properties of the blends are studied. The ISAF N231 type of carbon black shows a significant effect on tensile, tear and modulus properties by reacting at the interface between SBR/NR matrixes. The dynamic characteristics and storage modulus of SBR/NR with SAF N110 and SRF N774 types of carbon black show distinct characteristics in respect to all other blends in this system. The thermal stability of the rubber vulcanizates containing SAF N110 and SRF N774 types of carbon blacks is higher than other blend types. With the increasing percentage of SBR to NR, the thermal stability of the blend is increased. However, the heat buildup of the blends increases with the increase in SBR percentage.