Effect of Carbon Black/Silica Hybrid Filler on Thermal Properties,Fatigue Life,and Natural Weathering of SBR/Recycled NBR Blends

The utilization of nitrile glove waste will spark a great deal of interest in the rubber industry in developing cost-effective techniques to convert waste and used rubber into a processable form. Blends of styrene butadiene rubber/recycled acrylonitrile butadiene rubber (SBR/NBRr) reinforced at 85/15 blend with different ratios of a carbon black/silica (CB/Sil) hybrid filler (50/0, 40/10, 30/20, 20/30, 40/10, 0/50 phr) were tested either with or without the silane coupling agent, Si69. Results showed that the increased thermal stability of blends with Si69 is highly related to the formation of crosslinks between the filler. Thermogravimetric (TG) thermograms showed that the percentage of char residue for blends with Si69 was higher than without Si69. The differential scanning calorimetry (DSC) thermograms of both blends revealed a glass transition temperature (Tg) between 65.0°C and 66.9°C. At all blend ratios, the fatigue life of blends with Si69 was better than blends without Si69. After six months’ exposure to natural weather, blends with Si69 exhibited better tensile properties, retention, and morphology compared to blends without Si69.     

Curing Characteristics and Mechanical and Morphological Properties of Styrene Butadiene Rubber/Virgin Acrylonitrile-Butadiene Rubber (SBR/vNBR) and Styrene Butadiene Rubber/Recycled Acrylonitrile-Butadiene Rubber (SBR/rNBR) Blends

Curing characteristics and mechanical and morphological properties of styrene butadiene rubber/virgin acrylonitrile-butadiene rubber (SBR/vNBR) and styrene butadiene rubber/recycled acrylonitrile-butadiene rubber (SBR/rNBR) were investigated. Results indicated that the curing characteristics, such as scorch time, t₂, and cure time, t₉₀, of SBR/vNBR and SBR/rNBR blends decreased with increasing vNBR and rNBR content. At similar blend ratios, particularly up to 15 phr, SBR/rNBR blends exhibited higher t₂ and t₉₀ compared with SBR/vNBR blends. Minimum torque (ML) and maximum torque (MH) of SBR/vNBR blends significantly increased with increasing vNBR content. For SBR/rNBR blends, ML increased with increasing rNBR content, but MH exhibited the opposite trend. Tensile strength, elongation at break (E_b), resilience, and fatigue decreased with increasing virgin and recycled NBR content in both blends. Up to 15 phr, the tensile strength, E_b and fatigue life (Kc) of SBR/rNBR blends were higher than in SBR/vNBR blends. The M100 (stress at 100% elongation), hardness, and cross-linking density of both blends also showed an increasing trend with increasing vNBR and rNBR content. The scanning electron microscopy study indicates that rNBR exhibited a weak rNBR-SBR matrix interaction particularly when more than 15 phr of rNBR was used, thus decreasing the mechanical properties of SBR/rNBR blends.     

Effects of Natural Weathering on Properties of Recycled Newspaper-filled Polypropylene (PP)/Natural Rubber (NR) Composites

Natural weathering has been applied to investigate the properties of recycled newspaper (RNP)-filled polypropylene (PP)/natural rubber (NR) composites. Three sizes of RNP (11 mm, 23 mm, and 53 mm) were used in this study. These composites were subjected to natural weathering conditions; i.e, tropical climate in Penang, Malaysia, for 3 and 6 months. Different techniques including mechanical tests, Fourier transform infrared spectrometry (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were used in order to obtain a comprehensive view of degradation occurring during the natural weathering of the composites. Results of mechanical tests show that an increasing content of RNP in composites decreased the tensile strength and elongation at break (EB), while increasing the Young's modulus after exposure of 3 and 6 months. Scanning electron microscopy on surfaces after weathering shows that the filler was poorly wetted by the matrix. This explains the reduction in tensile strength and elongation at break after weathering. The Fourier transform infrared spectrometry results on the composites after exposure to natural weathering indicate the presence of carbonyl, vinyl, and hydroxyl groups, which formed from various chemical reactions taking place during weathering.     

Natural Weathering Test of Styrene Butadiene Rubber and Recycled Acrylonitrile Butadiene Rubber (SBR/NBRr) Blends

The effect of recycled acrylonitrile butadiene rubber (NBRr) content of SBR/NBRr blends on natural weathering was studied. Three different size of NBRr (S1; 117–334 µm, S2; 0.85–15.0 mm and S3; direct sheeted form) were used and the blends were exposed to natural weathering for 3 and 6 months. The results indicated that the SBR/NBRr blends with smallest size of NBRr (S1) show a better retention of tensile properties, which are able to withstand better weathering than coarser size (S2 and S3) of SBR/NBRr blends. The presence of hydroxyl, carbonyl and nitro group after exposure to natural weathering was detected in FTIR analysis, which related to the UV oxidation process of rubber blends. The scanning electron microscopy proved that the SBR/NBRr blends with smallest size of NBRr (S1) with higher content of NBRr, shows a better resistant to natural weathering.     

增容剂对PP/回收PET共混物性能的影响

采用熔融共混的方法,制备了聚丙烯(PP)/回收聚对苯二甲酸乙二酯(r-PET)共混物,研究了增容剂甲基丙烯酸缩水甘油酯接枝聚丙烯(PP-g-GMA)对共混物力学性能、热稳定性的影响。结果表明:增容剂的加入能提高共混物的拉伸强度和拉伸模量;加入增容剂能显著提高共混物的热分解温度,增容剂使r-PET的熔点降低;增容剂对PP的结晶性能影响与熔融温度有关。     

SBR/BR共混物的动态特性研究

对SBR1502/SBR1712/BR9000共混物的动态特性进行了研究。结果表明,三种聚合物的相容性较好;SBR1502和SBR1712两种聚合物的分子柔性和抗湿滑性能基本相同,但生热特性不同;tanδ和Tg可以通过控制共混物各组分的用量来调节,以获得具有不同滞后生热和抗湿滑性能的胶料。     

乙丙橡胶与低顺丁橡胶、甲基丁苯橡胶的并用研究

通过乙丙橡胶与低顺丁橡胶或甲基丁苯橡胶的并用，研究了并用胶料的压缩耐寒系数、恒定压缩永久变形、耐热空气老化等性能。结果表明，并用低顺丁橡胶、甲基丁苯橡胶可以显著提高乙丙橡胶的压缩耐寒系数。当低顺丁橡胶或甲基丁苯橡胶并用比例为30％时，在-50℃下的压缩耐寒系数由0．05提高到0．2以上；低顺丁橡胶含量增加，恒定压缩永久变形降低，但甲基丁苯橡胶的含量对恒定压缩永久变形影响不大；低顺丁橡胶或甲基丁苯橡胶并用比例的增加，并用胶的拉伸强度和拉断伸长率下降，耐热空气老化性能降低。     

丁腈橡胶与丁苯橡胶共混胶的性能研究

该文研究了丁腈橡胶与丁苯橡胶并用胶的性能,探讨了用丁苯橡胶替代部分丁腈橡胶的可能性。结果表明,丁腈橡胶中添加一定量丁苯橡胶对力学性能并没有太大的影响,在某些方面还有提高。对耐油性要求高的橡胶制品,可以少量加入丁苯橡胶,对耐油性影响不大,并可降低成本。对胶料进行了动态热机械分析（DMA）试验,通过对tgδ-温度图分析得出,加入丁苯橡胶可以改善丁腈橡胶的耐疲劳性。但是抗蠕变性下降。     

抗氧剂GM对SBR/HAF共混胶耐热老化性能的影响

研究了抗氧剂GM对SBR/HAF共混胶的硫化特性、力学性能和耐热老化性能的影响,并通过TG分析表征共混胶的耐热稳定性.结果表明,抗氧剂GM具有防止焦烧和软化胶料的作用,随着GM用量的增大,共混胶的伸长率和撕裂强度升高,硬度下降.共混胶的耐热老化性能随抗氧剂GM用量增大而提高,GM用量以3份为宜.TG分析表明,加入抗氧剂...     

回收高密度聚乙烯/废胶粉共混体系的力学性能研究

探讨了废胶粉（WRP）和回收高密度聚乙烯（RHDPE）共混改性时废胶粉的质量分数、相容剂的种类以及胶粉改性剂对RHDPE／WRP共混体系力学性能的影响。实验结果表明,当废胶粉的质量分数为20％时,体系的综合力学性能最佳。在RHDPE／WRP体系中分别添加EPDM、EVA、EAA时,EVA的增容效果最好,添加5％的EVA能使RHDPE／EVA／WRP体系的冲击强度增加55％。废胶粉经自制表面改性剂ACDI预处理后,其相应的RHDPE／EVA／MWRP体系的拉伸强度和弯曲模量分别增加35％和25％,而对共混物的其它性能影响不大。     

NBR/HNBR共混胶性能的研究

研究了NBR/HNBR共混比对其共混胶硫化特性、力学性能、耐热空气老化性能及耐臭氧性能的影响。结果表明,随着HNBR用量的增大,共混胶硫化时间先缩短后延长,力学性能先降低后升高,耐热空气老化性能提高,耐臭氧老化性能也提高。     

航空涂层材料大气暴露试验评价

航空涂层材料在拉萨大气试验站进行了大气暴露试验,通过对七组试板的老化数据分析,对涂层体系和颜料体系进行评价,以无机颜料为主的涂层系统的耐候性明显好于以有机颜料为主的涂层系统。     

表面活性剂增容PVC／SBR共混体系力学性能研究

通过冲击试验，应力－应变试验研究了表面活性剂用量，液体石蜡用量，注体石蜡用量，橡胶含量对ＰＶＣ／ＳＢＲ共混材料力学性能的影响。同时对表面活性剂增容ＰＶＣ／ＳＢＲ共混材料的形变机理进行了初步探讨。     

NBR/CM并用胶性能的研究

研究了在过氧化物硫化体系和硫黄硫化体系下,丁腈橡胶(NBR)/氯化聚乙烯橡胶(CM)并用比对力学性能、老化性能和耐油性能的影响.结果表明,随着CM用量的增加,过氧化物硫化胶的拉伸强度、100%定伸应力及硬度均呈增大趋势,而拉断伸长率、撕裂强度和压缩永久变形都略有增大;硫黄硫化胶的拉伸强度、拉断伸长率和撕裂强度均变化不大...     

表面活性剂增容PVC／SBR共混体系相容性研究

本文通过ＤＳＣ、振簧仪研究了聚氧化乙烯类表面活性剂作为增容剂对ＰＶＣ／ＳＢＲ共混物相容性的影响，并用扫描电镜（ＳＥＭ）观察了ＰＶＣ／ＳＢＲ共混物中橡胶分散相的形态结构和尺寸变化。结果表明，在ＰＶＣ／ＳＢＲ共混物中加入适量的表面活性剂可明显改善两相的相容性，橡胶分散相尺寸随表面活性剂用量、液体石蜡用量的变化而变化。     

Compatibilization Effects of PE-g-MA on Mechanical,Thermal and Swelling Properties of High Density Polyethylene/Natural Rubber/Thermoplastic Tapioca Starch Blends

Effect of polyethylene grafted maleic anhydride (PE-g-MA) on mechanical, thermal and swelling characteristic of high density polyethylene (HDPE)/natural rubber (NR)/thermoplastic tapioca starch (TPS) blends were studied. The measurements from differential scanning calorimetric (DSC), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), proved the effectiveness of PE-g-MA as compatibilizer in improving the miscibility between HDPE/NR – TPS blends. A decrement in crystallinity index was found after adding PE-g-MA. It is due to restriction in mobility of the HDPE chains. In the presence of PE-g-MA, the blends have better thermal stability. On top of that, the storage modulus which is reflected to the blend stiffness also increased as indicated the improvement in HDPE/NR – TPS interaction.     

玄武岩纤维对NR/SBR并用胶性能的影响

研究玄武岩纤维用量对天然橡胶/丁苯橡胶并用胶硫化特性、物理性能和动态力学性能的影响。结果表明:玄武岩纤维能够明显缩短并用胶的焦烧时间和正硫化时间;当玄武岩纤维用量小于10份时,无机填料分散性较好,并用胶综合物理性能变化较小;当玄武岩纤维用量大于10份时,各项物理性能下降明显;增大玄武岩纤维用量,并用胶的Payne效应增强,加工性能下降。     

Comparison of Properties of Polypropylene (PP)/Virgin Acrylonitrile Butadiene Rubber (NBRv) and Polypropylene (PP)/Recycled Acrylonitrile Butadiene Rubber (NBRr) Blends

The comparison properties of polypropylene (PP)/recycled acrylonitrile butadiene rubber (NBRr) blends and polypropylene/virgin acrylonitrile butadiene rubber (NBRv) blends were investigated. The tensile properties such as tensile strength, tensile modulus and elongation at break of PP/NBRv blends are higher than PP/NBRr blends. However, PP/NBRv blends exhibit lower stabilization torque and higher swelling percentage than PP/NBRr blends. Based on SEM, a finer morphology was observed in PP/NBRv blends in comparison with the PP/NBRr blends. The thermal stability of PP/NBRr is better than that of PP/NBRv blends.     

Influence of Recycled ABS Added to Virgin Polymers on the Physical,Mechanical Properties and Molding Characteristics

Reuse of recycled polymers is steadily increasing. In this study, two different ABS virgin materials are considered. Then, blends of varying proportions of ABS recycled resins (0–50%), obtained from the gate and runner materials of products, was added to virgin resin to investigate the effect of various compositions of virgin ABS and recycled polymers on the physical and mechanical properties of the final blend. Three different rib and closure organization of boss of the reinforcement structures were designed and injection molded under blends of varying proportions of the ABS recycled resins to do the torsion test by Air-Torsion tools. In addition, molding characteristics were also examined. The results show that there is no obvious effect of recycled ABS percentage (by weight) on the tensile strength, elongation at yield, flexural strength, flexural modulus, and impact strength. However, the torsion strength for rib and closure organization of boss of the reinforcement structures decrease with increasing recycled ABS weight percentage. On the other hand, hardness, glass transition temperature, and melting flow index of recycled ABS increase with as the percentage (by weight) of recycled material increase. The impact strength was found to vary with the recycled ABS loading. The injection pressure decreases with increasing the content of recycled resin under some specified molding conditions.     

TPI及SBR/TPI并用胶结晶特性的研究

使用差示扫描量热仪(DSC)研究了纯TPI粉末与SBR/TPI并用胶的结晶特性。结果表明,TPI粉末的第1次升温曲线上,β晶体的熔融温度随升温速率的增大逐渐提高,α晶体熔融峰高于β晶体;消除热历史后,β晶体熔融峰高于α晶体,且α晶体随着升温速率的提高逐渐消失;与第1次测试结果相比,第2次升温测得的结晶度呈下降趋势。冷冻作用能够稍微增大未填充SBR/TPI并用胶的结晶度。升温速率对未填充SBR/TPI并用胶晶体熔融峰的峰形分辨率有较大影响。随着TPI用量的增大,未填充并用胶及其硫化胶的结晶熔融焓均增大。填充炭黑后,SBR/TPI并用胶及其硫化胶都比未填充时的峰形钝化变宽。