粘土/NBR纳米复合材料的结构与性能研究

采用共絮凝粘土水悬浮液与NBR胶乳共混的方法制备了粘土／NBR纳米复合材料。透射电子显微镜观察表明粘土具有平面取向的纳米分散结构；X光衍射测试表明复合材料中还存在一定量的粘土片层聚集体；随着粘土用量的增大，复合材料的邵尔A型硬度、100％定伸应力、300％定伸应力、拉伸强度和扯断永久变形增大，扯断伸长率变化不大；粘土／NBR纳米复合材料的耐老化性能略优于白炭黑／NBR硫化胶；粘土可提高复合材料的气体阻隔性能，但对复合材料的氧指数影响不大。     

环氧化天然橡胶改性的丁苯橡胶/白炭黑复合材料的形态和性能

以环氧化天然橡胶为改性剂制备了丁苯橡胶/白炭黑复合材料,研究了环氧化天然橡胶对丁苯橡胶/白炭黑复合材料微观形态和力学、耐热、耐老化及动态力学性能的影响.结果表明,少量环氧化天然橡胶的加入改善了填料在橡胶基质中的分散,提高了丁苯橡胶/白炭黑复合材料硫化胶的定伸应力、拉伸强度、撕裂强度和耐磨性能,降低了其动态压缩疲劳生热速...     

纳米黏土/天然橡胶复合材料结构和性能研究

本研究采用机械共混法制备纳米黏土/天然橡胶(NR)复合材料,与白炭黑对比研究了该复合材料的加工性能、物理机械性能和动态性能等。结果表明,纳米黏土/NR复合材料与白炭黑增强橡胶相比,分散性好、门尼黏度低、抗焦烧性能好,便于加工;补强性能好,复合材料具有良好的物理机械性能;散热性、耐磨性好。     

炭黑/稻壳源白炭黑并用对天然橡胶增强作用的粒径效应

考察了不同粒径炭黑与稻壳源白炭黑并用对天然橡胶(NR)性能的影响。结果表明,随着炭黑粒径的增大,炭黑/稻壳源白炭黑增强NR混炼胶的门尼黏度、最低转矩及最高转矩均变小,加工性能变好。随着炭黑粒径的增大,炭黑/稻壳源白炭黑增强NR硫化胶的拉伸强度降低,邵尔A硬度减小,耐磨性能及耐老化性能变差。N 330与稻壳源白炭黑并用增强NR具有较好的耐寒性能和抗湿滑性能,较低的滚动阻力。     

补强体系对天然橡胶减振材料性能的影响

研究补强体系对天然橡胶减振材料性能的影响。结果表明：填充19份炭黑N774和39份白炭黑的胶料的拉伸强度、拉断伸长率和撕裂强度最大,但填料分散性和耐老化性能差,压缩永久变形较大;填充37份炭黑N550和19份炭黑N774胶料的交联密度和拉伸强度最小,Payne效应强,压缩永久变形最大;填充43份炭黑N774或39份炭黑N660及20份白炭黑的胶料兼具优异的填料分散性和耐老化性能,且压缩永久变形较小,可满足减振橡胶材料的性能要求。     

湿法改性高岭土与不同填料在SBR中的应用

将湿法改性高岭土与未改性高岭土、炭黑、白炭黑以及碳酸钙分别填充到SBR中制备复合材料,并对其性能进行了研究。结果表明,炭黑填充SBR复合材料的综合性能最好,改性高岭土次之,白炭黑填充略好于高岭土填充,碳酸钙填充的性能最差;与未改性高岭土相比,改性高岭土胶料的加工性能得到改善,拉伸强度、定伸应力、撕裂强度均增大,耐磨性及耐老化性能变好。     

黏土/天然橡胶纳米复合材料在矿用轮胎胎面胶中的应用

用黏土/天然橡胶纳米复合材料代替部分进口天然橡胶和炭黑制备抗崩花掉块和耐破坏的高性能的矿山轮胎胎面胶。结果表明,纳米黏土基本不影响胶料的硫化性能;纳米黏土构建网络结构的能力较强,Payne效应明显,黏土复合体系的混炼胶具有较好的挺性,硫化胶具有较高的硬度和定伸应力;纳米黏土片层能够沿外力方向取向并诱导高分子链取向,黏土复合体系的断裂伸长率较高,拉伸强度和撕裂强度较大,生热较高,同时纳米黏土的片层结构能够钝化支化裂纹尖端,复合体系的耐切割和耐屈挠裂纹增长性能优异。成品轮胎的路试结果表明,黏土/天然橡胶纳米复合材料完全可以代替进口天然橡胶用于矿山专用全钢载重子午线轮胎胎面胶配方中。     

分散剂Zr-201在橡胶中的应用研究

考察了新型硼酸酯分散剂Zr-201对天然橡胶胶料加工性能和胎面胶物理机械性能的影响。结果表明,Zr-201具有增塑作用,能降低NR混炼能耗和排胶温度,降低胶料的粘度,提高流动性;能改善NR的挤出特性,减小挤出口型膨胀,提高挤出物的表面光滑程度;Zr-201能提高N330炭黑在NR中的分散性;能缩短硫化时间和焦烧时间;Zr-201能明显提高胎面胶的撕裂强度,能提高硫化胶的拉伸强度、拉断伸长率和拉伸永久变形,降低定伸应力,硬度和耐老化性,对耐磨性影响不大。     

改性凹土/NBR/HSR纳米复合材料的制备及性能研究

采用机械共混法制备改性凹土(AT)/丁腈橡胶(NBR)/高苯乙烯树脂(HSR)纳米复合材料,研究了改性AT部分替代白炭黑对复合材料硫化特性、力学性能、耐磨性、耐介质及热老化等性能的影响,并与白炭黑,或碳酸钙、碳酸镁部分替代白炭黑填充胶料的性能进行了对比;结果表明,改性AT的加入能提高胶料的硬度、300％定伸应力、撕裂强度以及耐热老化性能,改性AT填充胶的拉伸强度、伸长率、耐磨性、耐介质性能与白炭黑填充NBR/HSR胶料的性能相近,但总体明显高于碳酸钙、碳酸镁部分替代白炭黑胶料的性能,说明改性AT具有很好的补强作用.     

熔体法制备有机黏土/橡胶纳米复合材料的结构及性能

将有机黏土(OC)分别加入到天然橡胶(NR)、丁苯橡胶(SBR)、丁基橡胶(IIR)和三元乙丙橡胶(EPDM)中,通过熔体法制备了纳米复合材料。探讨了橡胶黏度及其分子结构对OC在复合材料中分散状况的影响,研究了复合材料的力学性能。结果表明,在以NR为基体的复合材料中。OC片层分散均匀,且剥离程度较高;在SBR,IIR,EPDM中,OC以插层结构为主,且插层效果从大到小的顺序依次为SBR,IIR,EPDM。与相应的纯胶相比,OC／NR纳米复合材料的定伸应力提高,拉伸强度和扯断伸长率有所下降;OC／SBR,OC／IIR,OC／EPDM纳米复合材料的定伸应力变化不大,拉伸强度和扯断伸长率明显提高,且OC／SBR和OC／EPDM复合材料的撕裂强度提高。     

SBR-clay-carbon black hybrid nanocomposites for tire tread application

Styrene butadiene rubber-organoclay nanocomposites were prepared with Cloisite 15A via melt intercalation. X-ray diffraction and transmission electron microscopy indicated that the nanostructures are partially exfoliated and intercalated. The nanocomposites exhibited great improvements in tensile strength and tensile modulus. The incorporation of organoclay gave rise to considerable reduction of tan delta and increase in storage modulus in the rubbery region. It is shown that after 6 phr (parts per hundred rubber) clay loading there is not much increase in the properties. The effect of carbon black (N330) on mechanical properties, dynamic mechanical properties, heat build up, abrasion resistance in the nanocomposites having the optimized clay level (6 phr) was investigated. Optimum results were obtained with the addition of 25 phr carbon black. For comparison with the 6phr nanoclay and 25phr N330 (high abrasion furnace carbon black) filled SBR composites, 40 phr N330 filled SBR composites was used. The 6phr organoclay and 25phr N330 filled SBR nanocomposite showed better properties than 40phr carbon filled SBR compound. These results indicate that 6phr organoclay can be replaced by 15 phr carbon black from the conventional SBR-carbon black based tire tread compounds. The Dynamic mechanical analyzer (DMA) results revealed that the new tire tread compound gives better rolling resistance and comparable wet grip resistance and lower heat build up than that of conventional tread compound.     

新型白炭黑对天然橡胶性能的影响

研究自制新型白炭黑对天然橡胶(NR)性能的影响,并与市售白炭黑进行对比。结果表明:与市售白炭黑NR胶料相比,自制白炭黑NR胶料的硫化时间缩短,拉伸强度、拉断伸长率、弹性和耐磨性能较好,生热较低,耐屈挠龟裂性能相当;自制白炭黑用量为30份时胶料综合性能最佳。     

Improved mechanical properties of natural rubber composites reinforced by novel SiO2@HCNFs nanofillers at a low filler loading

In order to improve high reinforcement properties of natural rubber (NR), SiO₂@HCNFs as novel double-phase nanofillers at low content have been loaded in NR by using mechanical mixing method. The morphologies and structures of SiO₂@HCNFs and NR composites were characterized, and the performances of NR composites were measured. The results show that compared with pure N330/NR, the modulus at 300% strain, tensile strength, elongation at break of NR composites increase by 10.7, 17.9, and 9.0%, respectively, at only 2.5 phr SiO₂@HCNFs content. Meanwhile, the volume abrasion of NR composites is also dramatically reduced at 2.5 phr SiO₂@HCNFs content, about 53.4% less than that of N330/NR, though the shore hardness increases by only 3.7%. It is also found that NR composites reinforced by SiO₂@HCNFs at 2.5 phr content have much higher hardness and abrasion performance than HCNFs/NR. The DMA results show that high wet skid resistance and low rolling resistance of NR composites were also achieved by loading 6.5 phr SiO₂@HCNFs. The unique structure of SiO₂@HCNFs double-phase nanofillers plays a crucial role in properties of NR composites, in virtue of the significant synergetic reinforcing effect of both HCNFs and silica.     

Fracture properties of silica/carbon black-filled natural rubber vulcanizates

Crack growth property of natural rubber (NR) vulcanizate with varying silica/carbon black content was examined. Tensile specimen with edge cut was used for estimating fracture properties. All filled NR specimens showed critical cut-size (C _cr ), which is related to abrupt decrease in tensile strength. Carbon black-filled NR, S0 (Si/N330=0/50) has higher tensile strength than equivalently loaded silica-filled NR vulcanizates, S5 (Si/N330=50/0). When the precut size of specimen was less than critical cut-size, tensile strength of S1 (Si/N330=10/40) composition was the highest and that of S5 was the lowest. The critical cut-size passes through a maximum for S2 (Si/N330=20/30) and then decreases gradually with silica loading. An interesting result was that silica and carbon black-blended compounds gave higher critical cut size than the all-carbon black compounds, S0. The inherent flaw size decreased from 246 μm for S0 to 80 μm for S5 as the silica content increased.     

不同硫化体系对天然橡胶的动静态性能的影响研究

分别制备了以炭黑和白炭黑为补强填料的不同硫化体系天然橡胶(NR)复合材料,研究硫化体系对NR胶料静态和动态性能的影响。结果表明:普通硫化体系硫化胶具有较高的交联密度、较好的物理性能和优异的耐磨性能;对于白炭黑补强体系,普通硫化体系硫化胶具有最低的滚动阻力;而对于炭黑补强体系,平衡硫化体系硫化胶具有最低的滚动阻力;胶料拉伸强度的增大有利于耐磨性的提高。     

Effect of carbon black on properties of rubber nanocomposites

Polymer based nanocomposites were prepared using brominated poly(isobutylene‐co‐paramethylstyrene) (BIMS) rubber and octadecyl amine modified montmorillonite nanoclay. The effect of nature and loading of carbon black on these nanocomposites and the control BIMS was investigated thoroughly using X‐ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR), and mechanical properties. The addition of 4 parts of the modified nanoclay to 20 phr N550 carbon black filled samples increased the tensile strength by 53%. Out of the three different grades of carbon black (N330, N550, and N660), N550 showed the best effect of nanoclay. Optimum results were obtained with the 20 phr filler loading. For comparison, china clay and silica at the same loading were used. Fifty‐six and 46% improvements in tensile strength were achieved with 4 parts of nanoclay added to the silica and the china clay filled samples, respectively. N330 carbon black (20 parts) filled styrene butadiene rubber (SBR) based nanocomposite registered 20% higher tensile strength with 4 parts of the modified nanoclay. In all the above carbon black filled nanocomposites, the modulus was improved in the range of 30 to 125%. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 443–451, 2005     

Structure and properties of strain‐induced crystallization rubber–clay nanocomposites by co‐coagulating the rubber latex and clay aqueous suspension

Natural rubber (NR)–clay (clay is montmorillonite) and chloroprene rubber (CR)–clay nanocomposites were prepared by co‐coagulating the rubber latex and clay aqueous suspension. Transmission electron microscopy showed that the layers of clay were dispersed in the NR matrix at a nano level, and the aspect ratio (width/thickness) of the platelet inclusions was reduced and clay layers aligned more orderly during the compounding operation on an open mill. However, X‐ray diffraction indicated that there were some nonexfoliated clay layers in the NR matrix. Stress–strain curves showed that the moduli of NR were significantly improved with the increase of the amount of clay. At the same time, the clay layers inhibited the crystallization of NR on stretch, especially clay content of more than 10 phr. Compared with the carbon‐black‐filled NR composites, NR–clay nanocomposites exhibited high hardness, high modulus, high tear strength, and excellent antiaging and gas barrier properties. Similar to NR–clay nanocomposites, CR–clay nanocomposites also exhibited high hardness, high modulus, and high tear strength. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 318–323, 2005     

补强体系对NR硫化胶疲劳破坏特性的影响

用断裂力学方法研究炭黑N330、炭黑N330/白炭黑和白炭黑补强NR硫化胶的疲劳破坏特性.结果表明,与炭黑N330和炭黑N330/白炭黑补强的NR硫化胶相比,白炭黑补强的NR硫化胶疲劳寿命较长,内部潜在缺陷较少,抗裂纹扩展性能较好;随着疲劳时间的延长,NR硫化胶拉断时的应变能密度减小;疲劳寿命方程能够快速、准确地预测NR硫化胶的疲劳寿命.     

Preparation,characterization, and application of NR/SBR/Organoclay nanocomposites in the tire industry

The natural rubber/styrene butadiene rubber/organoclay (NR/SBR/organoclay) nanocomposites were successfully prepared with different types of organoclay by direct compounding. The optimal type of organoclay was selected by the mechanical properties characterization of the NR/SBR/organoclay composites. The series of NR/SBR/organoclay (the optimal organoclay) nanocomposites were prepared with various organoclay contents loading from 1.0 to 7.0 parts per hundreds of rubber (phr). The nearly completely exfoliated organoclay nanocomposites with uniform dispersion were confirmed by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The results of mechanical properties measurement showed that the tensile strength, tensile modulus, and tear strength were improved significantly when the organoclay content was less than 5.0 phr. The tensile strength and the tear strength of the nanocomposite with only 3.0 phr organoclay were improved by 92.8% and 63.4%, respectively. It showed organoclay has excellent reinforcement effect with low content. The reduction of the score and cure times of the composites indicated that the organoclay acted as accelerator in the process of vulcanization. The incorporation of a small amount of organoclay greatly improved the swelling behavior and thermal stability, which was attributed to the good barrier properties of the dispersed organoclay layers. The outstanding performance of co‐reinforcement system with organoclay in the tire formulation showed that the organoclay had a good application prospect in the tire industry, especially for the improvement of abrasion resistance and the reduction of production cost. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation of nanocomposites by melt compounding polylactic acid/polyamide 12/organoclay at different screw rotating speeds using a twin screw extruder

This study analyzes the effect of different screw rotating speeds on the clay dispersion and mechanical properties of nanocomposites prepared by melt compounding polylactic acid (PLA) with an organoclay in a co‐rotating twin screw extruder. Polyamide 12 (PA12) was used as an additive. Two different screw rotating speeds, 65 rpm and 150 rpm, were used in this study. According to the tensile strength data, the Young's modulus of the PLA/clay nanocomposites showed improvement at a screw rotating speed of 150 rpm. The Young's modulus improved with the addition of the organoclay to PLA matrix, but decreased when PA12 was added to the PLA matrix. The tensile strengths and elongations become small by adding organoclay to PLA matrix. The tensile strengths of the PLA/organoclay nanocomposites increased for the higher screw rotating speed (150 rpm). The d‐spacing of PLA/PA12/Clay nanocomposites was independent of the addition of PA12. The size of the clay aggregates in the PLA/PA12/Clay nanocomposites is smaller than that of PLA/Clay. Furthermore, the thermal stability of the PLA/Clay nanocomposite increases with addition of PA12, while on the whole, it had little influence on the tensile properties. POLYM. COMPOS., 29:1–8, 2008. © 2007 Society of Plastics Engineers