丁腈橡胶/聚酰胺热塑性弹性体的制备及性能

采用Haake密炼机工艺、开炼机工艺和开炼机预混-Haake密炼机工艺制备了丁腈橡胶（NBR）／聚酰胺（PA）热塑性硫化胶（TPV）,研究了NBR／PATPV的结晶结构及其性能。结果表明,采用开炼机预混-Haake密炼机工艺可制得相态结构均匀、分散相粒径较小、力学性能和耐溶剂性能较好的NBR／PATPV。在NBR／PATPV中,NBR可诱发PA结晶。PA连续相结晶结构分布的均匀性和相界面之间的相互作用是提高NBR／PATPV耐溶剂性能的主要因素。     

Thermoplastic elastomer blend based on EMA and NBR; optimization of process parameters

EMA–NBR has been explored to be a potential thermoplastic elastomer blend having good thermal stability as well as oil resistance property. The present investigation reports the optimization of process parameters for the novel polymer blends based on poly(ethylene-co-methyl acrylate) (EMA) and poly(acrylonitrile-co-butadiene) rubber (NBR) with criteria based on the statistical design of experiment (Taguchi L9 orthogonal array). In this case, the polymer blends were prepared by changing the polymer blending conditions such as mixing temperature, mixing time and rotor speed as per Taguchi's L9 orthogonal array. Optimization of the process parameters was carried out based on the physicomechanical properties such as tensile strength, elongation at break, hardness, and tensile impact strength of the resulting EMA/NBR blend. Each processing parameter has been optimized from the experimental data, which are converted into signal-to-noise ratio. The standard statistical technique of analysis of variance result was used to evaluate the proportional role of the different control variables. It has been found that the mixing temperature play very significant role trailed by rotor speed and mixing time in controlling droplet matrix morphology of the EMA/NBR blends. Predominantly, these factors affect the size of the NBR domain and its distribution in the EMA matrix, which in turn have a notable contribution to the physicomechanical properties of the blends. By the optimization of processing conditions, the NBR matrix domain size greatly decreases, leading to significant improvement in physicomechanical properties of the EMA/NBR blends. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48900.     

Optimizing mechanical and morphological properties of biodegradable thermoplastic elastomer based on epoxidized natural rubber and poly(butylene succinate) blends

Biodegradable thermoplastic elastomer (BTPE) blends of epoxidized natural rubber (ENR) and poly(butylene succinate) (PBS) were prepared by the melt mixing process. Influences of the processing parameters mixing temperature, rotor speed, and mixing time on mechanical and morphological properties of BTPE were investigated. Taguchi method was applied to improve the mechanical and morphological properties by optimizing the processing parameters. That is, the experimental design adopted the L9 Taguchi orthogonal array with three manipulated factors (i.e., mixing temperature, rotor speed, and mixing time). Analysis of mean and analysis of variance were also exploited and the mixing temperature was found to be the most significant processing parameter regarding mechanical properties. The mixing temperature showed large contributions to Young's modulus, 100% modulus, tensile strength, and elongation at break, namely 45.33, 40.38, 49.31, and 36.04%, respectively. Furthermore, the optimum conditions found for mixing temperature, rotor speed, and mixing time were 140 °C, 100 rpm and 10 min, respectively. The result was confirmed by atomic force microscopy and scanning electron microscopy micrographs showing fine‐grained co‐continuous phase morphology of the ENR/PBS blends. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46541.     

动态硫化丁腈橡胶/尼龙6热塑性弹性体的制备及性能

采用动态硫化法制备了丁腈橡胶/尼龙6热塑性弹性体(NBR/PA 6 TPV),考察了硫化体系、羧基丁腈橡胶(XNBR)以及增塑剂高密度氧化聚乙烯蜡(AC-316 A)和正丁基苯磺酰胺(BBSA)对TPV硫化特性、力学性能和微观形貌的影响。结果表明,以促进剂HVA-2/促进剂DM为硫化体系,动态硫化过程体系黏度的变化比以酚醛树脂/SnCl2为硫化体系时更平稳;但用后者制备TPV,其撕裂强度和扯断伸长率等力学性能更优,PA 6的结晶度更低。XNBR能对NBR和PA 6起到增容作用,当XNBR与NBR的质量比为10/90时,TPV的力学性能最好,NBR在PA 6中分散得最均匀。AC-316 A和BBSA都能对TPV起到增塑作用,随其用量的增加,体系黏度降低。     

耐油性PA6/NBR共混物的制备与性能研究

采用不同种类的丁腈橡胶(NBR)与聚酰胺6(PA6)熔融共混制备了聚酰胺6/丁腈橡胶混合物(PA6/NBR),考察了共混过程中转矩值的变化,并研究了不同腈基含量共混物的拉伸性能及耐溶剂性能。结果表明,随着橡胶相含量的增加,共混物的熔体黏度、体积溶胀率与质量溶胀率均显著提高,但拉伸强度下降。红外光谱分析表面NBR与PA6在高温高剪切作用下存在微化学反应,并且随腈基含量的增加,PA6/NBR共混物的平衡转矩值增大,拉伸强度明显提高,耐溶剂性下降。     

Effect of the processing parameters on the surface resistivity of acrylonitrile–butadiene rubber/multiwalled carbon nanotube nanocomposites

In this study, acrylonitrile–butadiene rubber (NBR) was melt‐mixed with multiwalled carbon nanotubes (MWCNTs). Because the electrical conductivity and mechanical properties of composites are strongly influenced by the filler's state of dispersion and the extent of filler breakage during processing, the processing conditions are very important parameters. The effects of the mixing time, rotor speed, cooling rate, and sulfur concentration on the surface resistivity were investigated. Increasing the rotor speed from 20 to 60 rpm at mixing times of 15 and 30 min led to an increase in the surface resistivity from around 10⁴ to 10¹¹ Ω/square. However, at a mixing time of 7 min, the surface resistivity slightly decreased with increasing rotor speed. When slow cooling was applied, a surface resistivity of 10⁴ Ω/square was obtained at around 2‐phr MWCNTs. However, when the fast cooling was applied, a surface resistivity of 10⁶ Ω/square was obtained at 5‐phr MWCNTs. The tensile strength and tensile modulus at 300% elongation were improved with the addition of MWCNTs into NBR. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effect of nanostructures of modified clay–carbon black on physico‐mechanical,electrical, and acoustic properties of elastomer‐based composites

Elastomeric composites based on nitrile rubber (NBR), carbon black (CB), and organically modified nanoclay (NC) were prepared using a laboratory two‐roll mixing mill. Influences of the hybrid filler system (CB+NC) on various properties of NBR compound were analyzed. It was found that the addition of hybrid filler (CB+NC) over only carbon black enhances various properties. It was also found that the addition of nanoclay to the rubber matrix effectively improved key properties. Acoustics and electrical properties were modified with reduced water absorption because of layered clay platelets. The lower volume resistivity of NBR composites reflected better electrical conductivity attributed to the presence of nanoclay leading to effective filler connectivity. X‐ray diffraction and transmission electron microscopy measurements revealed that nanoclays were mostly intercalated and were uniformly dispersed. Use of calcium stearate facilitated dispersion of nanoclay in the rubber matrix which was observed through the formation of nanostructures including “nano” and “halo” units. Time temperature superposition in dynamic mechanical analysis test of the composites indicated lower mechanical loss in the frequency range of interest. The advantages accruing due to overall property enhancement, including lower water absorption, and better electrical and excellent acoustic properties of NBR composites make it suitable as underwater acoustic transparent materials for transducer encapsulation application. POLYM. COMPOS., 37:1786–1796, 2016. © 2014 Society of Plastics Engineers     

Physical properties of polyamide 6/H‐NBR blends and the effects of dynamic vulcanization on them

Polyamide 6 (PA 6) and hydrogenated nitrile rubber (H‐NBR) were blended with various blend ratios in a brabender plasticoder at 240°C/100 rpm. The processing characteristics with a mixing torque of the blends were investigated. The effect of the blend ratio on physical properties such as tensile strength, Young's modulus, elongation at break, permanent set, hardness, and swelling behavior of blends was analyzed. Most mechanical properties were found to decrease with an addition of H‐NBR. The morphology of the blends was observed, and the results show a two phase system where the component with high proportions exists as a continuous phase. A cocontinuous phase was observed in blend ratios of 50/50 and 40/60. Dynamic mechanical properties were observed to study a viscoelastic property of the blends. In addition, the effect of dynamic vulcanization with peroxide on physical properties was studied, and the influence of peroxide on PA 6 was also examined. It was found that the peroxide can have an effect on PA 6 as well as act as a crosslinker to H‐NBR. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

三元共聚尼龙/聚氯乙烯/丁腈橡胶三元共混弹性体研究

选择三元共聚尼龙（PA），聚氯乙烯（PVC）和丁腈橡胶（NBR）为主体材料，采用高温机械共混，化学交联工艺制得了PA／PVC／NBR三元共混弹性体，探讨了PA／NBR，POM／NBR，PVC／NBR，HMWPVC／NBR三元共混体系性能，重点讨论了PA／PVC／NBR共混比，不同硫化体系，有机过氧物DCP用量等因素对PA／PVC／NBR三元共混弹性体性能的影响，实验结果表明：选择适宜配方制得力学性能和耐油耐溶剂性能较好的PA／PVC／NBR三元共混弹性体，扫描电镜的实验结果证实m(PA):m(PVC):m(NBR)=10:30:60和m(PA):m(PVC):m(NBR)=30:10:60两个体系的三元共混弹性体均具有较好的相容性，且前者的相容性更好。     

Preparation of thermoplastic elastomer nanocomposites based on polyamide‐6/polyepichlorohydrin‐co‐ethylene oxide

This work is aimed at determining the effect of nanoclay and polyepichlorohydrin‐co‐ethylene oxide (ECO) content on the microstructure and mechanical properties of PA6/ECO thermoplastic elastomers (TPEs). TPE nanocomposites were prepared in a laboratory mixer using polyamide 6 (PA6), ECO, and an organoclay by a two‐step melt mixing process. First, the PA6 was melt blended with Cloisite 30B and then mixed by ECO rubber. X‐ray diffraction results and transmission electron microscopy image showed that the nanoclay platelets were nearly exfoliated in both the phases. The SEM photomicrograph of PA6 with ECO showed that the elastomer particles are dispersed throughout the polyamide matrix and the size of rubber particles is less than 3 μm. Introduction of organoclay in the PA6 matrix increased the size of dispersed rubber particles in comparison with the unfilled but otherwise similar blends. The nanoscale dimension of the dispersed clay results in an improvement of the tensile modulus of the nanocomposites. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers     

丁腈橡胶/聚酰胺热塑性硫化胶的制备

用橡塑预混法、二步法和母炼胶法制备了丁腈橡胶／聚酰胺热塑性硫化胶(NBR／PATPV),研究了3种工艺对NBR／PATPV相态结构、流变性能、物理机械性能和耐溶剂性能的影响。结果表明,NBR与PA在高温、高剪切作用下,两相界面之间可发生微化学反应,但并不影响动态硫化时两相之间的相态反转过程。用橡塑预混法可制得分散相粒径小且分布均匀的TPV,该TPV的100％定伸应力大,压缩永久变形小,耐溶剂性能不佳,表观黏度略大,但挤出物外观光滑。     

Natural rubber/nitrile butadiene rubber/hindered phenol composites with high-damping properties

New natural rubber (NR)/nitrile butadiene rubber (NBR)/hindered phenol (AO-80) composites with high-damping properties were prepared in this study. The morphological, structural, and mechanical properties were characterized by atomic force microscopy (AFM), polarized Fourier transform infrared spectrometer (FTIR), dynamic mechanical thermal analyzer (DMTA), and a tensile tester. Each composite consisted of two phases: the NR phase and the NBR/AO-80 phase. There was partial compatibility between the NR phase and the NBR/AO-80 phase, and the NR/NBR/AO-80 (50/50/20) composite exhibited a co-continuous morphology. Strain-induced crystallization occurred in the NR phase at strains higher than 200%, and strain-induced orientation appeared in the NBR/AO-80 phase with the increase of strain from 100% to 500%. The composites had a special stress–strain behavior and mechanical properties because of the simultaneous strain-induced orientation and strain-induced crystallization. In the working temperature range of a seismic isolation bearing, the composites (especially the NR/NBR/AO-80 (50/50/20) composite) presented a high loss factor, high area of loss peak (TA), and high hysteresis energy. Therefore, the NR/NBR/AO-80 rubber composites are expected to have important application as a high-performance damping material for rubber bearing.     

第三组分PCR对NBR／PVC共混胶性能的影响

将PCR（PE／CR=30／70）作为第三组分加入NBR/PVC共混体系中,能促使炭黑等配合剂快速均匀地分散,提高了混炼胶综合物理机械性能;阐述了PCR对NBR／PVC的共混相容性机理、共混过程中吃粉速度及对硫化胶性能的影响等。结果表明,PCR在合适的用量时,混炼胶吃炭黑时间比没加PCR时减少了一倍多,硫化胶拉伸强度、扯断伸长率、阿克隆磨耗以及与金属粘着强度等提高幅度均较大。     

Effects of Dynamic Vulcanization and Acrylic Acid on Properties of Recycled Poly(vinyl chloride)/Acrylonitrile Butadiene Rubber (PVCr/NBR) Blends

Effects of dynamic vulcanization and acrylic acid (AAc) on processability, mechanical properties, swelling behavior, morphology, and thermal stability of recycled poly(vinyl chloride)/acrylonitrile butadiene rubber (PVCr/NBR) blends were investigated. Blends were prepared in a Haake Rheomix at a temperature of 150°C and a rotor speed of 50 rpm. Recycled poly(vinyl chloride)/acrylonitrile butadiene rubber (PVCr/NBR) blends were also prepared as comparison. It was found that the dynamic vulcanization and the addition of acrylic acid improved the stabilization torque, mechanical energy, stress at peak, stress at 100% elongation (M₁₀₀), swelling resistance, and thermal stability but decreased the elongation at break of the blends. The introduction of a cross-link into the elastomer phase and better compatibility between PVCr and NBR are responsible for the enhancement of thermal stability and mechanical properties of dynamically vulcanized PVCr/NBR + AAc as evidence from the scanning electron microscopy (SEM) of the tensile fracture surfaces and infrared spectroscopy study of the dynamically vulcanized of PVCr/NBR + AAc shows.     

Effect of acrylic acid on the properties of recycled poly(vinyl chloride)/acrylonitrile–butadiene rubber blends

The effect of acrylic acid (AAc) on the torque, stabilization torque, mechanical energy, swelling behavior, mechanical properties, thermal stability, and morphological characteristics of recycled poly(vinyl chloride)/acrylonitrile–butadiene rubber (PVCr/NBR) blends was studied. The blends were melt mixed at a temperature of 150°C and rotor speed of 50 rpm. AAc was used to improve the compatibility of PVCr/NBR blends. Virgin PVCv/NBR blends were prepared to provide a comparison. It was found that PVCr/NBR + AAc blends exhibit higher stabilization torque, mechanical energy, stress at peak, and stress at 100% elongation, but lower elongation at break and swelling index than those of PVCr/NBR and PVCv/NBR blends. SEM study of the tensile fracture surfaces of the blends indicated that the presence of AAc increased the interfacial interaction between PVCr and NBR phases, thus improving the compatibility between PVCr and NBR phases. However, thermal gravimetry analysis of the blends showed that the presence of AAc decreased the thermal stability of PVCr/NBR blends. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2181–2191, 2005     

Mechanical Properties and Thermooxidative Aging of a Ternary Blend,Pvc/Enr/Nbr,Compared with the Binary Blends of Pvc

In the quest to improve the thermooxidative aging of the poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blend, nitrile rubber (NBR) was incorporated into the blend to yield a ternary blend of PVC/ENR/NBR. A Brabender Plasticorder with a mixing attachment was used to perform the melt mixing at 150°C and 50 rpm followed by compression molding. The mechanical properties, dynamic mechanical properties, and thermooxidative aging behavior of the ternary blend were compared with those of the binary blends (i.e., PVC/ENR and PVC/NBR). It was found that the ternary blend exhibits mechanical properties which are superior to those of PVC/ENR. A single glass transition temperature (T _g) obtained from dynamic mechanical analysis coupled with synergism in the modulus and some other mechanical properties indicate that PVC, ENR, and NBR form a single phase (miscible system) in the ternary blend. Di-2-ethyl hexylphthalate (DOP) plasti-cizer improves the aging resistance of the blends generally, whereas the presence of CaCO₃ as a filler only imparts minor influences on the properties and aging resistance of the blends.     

丁腈橡胶/聚氯乙烯/有机蒙脱土纳米复合材料的结构与性能

采用胶乳共沉法和直接共混法制备了丁腈橡胶／聚氯乙稀／有机蒙脱土（NBR／PVC／OMMT）纳米复合材料。通过X射线衍射（XRD）法和透射电子显微镜（TEM）法对NBR／PVC／OMMT纳米复合材料的结构进行了袁征,并研究了复合材料的力学性能、耐油性能和耐老化性能。结果表明,2种方法所获得的复合材料是插层型纳米复合材料;胶乳共沉法制备的纳米复合材料中OMMT的分散更为均匀,其力学性能、耐油性能和耐老化性能优于直接共混法制备的复合材料。     

Gasoline permeation behavior and mechanical properties of polyamide 6/nanoclay,polyamide 6/PE‐g‐maleic anhydride blend,and polyamide 6/PE‐g‐maleic anhydride/clay nanocomposite

In this article, polyamide 6 (PA6)/clay nanocomposites, PA6/polyethylene grafted maleic anhydride (PE‐g‐MA) blends, and PA6/PE‐g‐MA/clay nanocomposites were prepared and their gasoline permeation behavior and some mechanical properties were investigated. In PA6/clay nanocomposites, cloisite 30B was used as nanoparticles, with weight percentages of 1, 3, and 5. The blends of PA6/PE‐g‐MA were prepared with PE‐g‐MA weight percents of 10, 20, and 30. All samples were prepared via melt mixing technique using a twin screw extruder. The results showed that the lowest gasoline permeation occurred when using 3 wt % of nanoclay in PA6/clay nanocomposites, and 10 wt % of PE‐g‐MA in PA6/PE‐g‐MA blends. Therefore, a sample of PA6/PE‐g‐MA/clay nanocomposite containing 3 wt % of nanoclay and 10 wt % of PE‐g‐MA was prepared and its gasoline permeation behavior was investigated. The results showed that the permeation amount of PA6/PE‐g‐MA/nanoclay was 0.41 g m^?2 day^?1, while this value was 0.46 g m^?2 day^?1 for both of PA6/3wt % clay nanocomposite and PA6/10 wt % PE‐g‐MA blend. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40150.     

NBR╱PA热塑性弹性体的相态研究

对动态硫化法制备的丁腈橡胶/尼龙(NBR/PA)热塑性弹性体的相态和结晶行为,以及它们对材料性能的影响作了研究。透射电子显微镜观察表明,在NBR/PA为80/20～20/80(质量比)时,热塑性弹性体的连续相和分散相分别为PA和NBR,未出现相转变。分散相的粒径随NBR用量和交联度的提高而增大,粒径分布则随之变宽。差示扫描量热仪测定表明,动态硫化作用和增大NBR用量,均能降低PA的熔点和结晶度。共混体的结晶结构可以提高材料的弹性模量和拉伸强度。     

Effect of modified single‐wall carbon nanotubes on mechanical and morphological properties of thermoplastic elastomer nanocomposites based on (polyamide 6)/(acrylonitrile butadiene rubber)

Thermoplastic elastomer nanocomposites based on acrylonitrile butadiene rubber (NBR) and polyamide 6 (PA6), with acid functionalized single‐wall carbon nanotubes (SWNT), were prepared via a direct melt‐mixing process in an internal mixer. The influence of SWNT content (0, 0.5, 1, 1.5) on morphological properties of PA6/NBR with different ratios (80/20, 70/30, 60/40) were then investigated. Characterization of nanocomposites was conducted by using transmission electron microscopy, scanning electron microscopy, differential scanning calorimetry, and mechanical properties. Scanning electron microscopy micrographs proved the droplet‐matrix blend morphology in which the size of NBR droplets decreased as the SWNT loading increased, suggesting dispersion of SWNT in the PA6 phase. It was further proved by transmission electron microscopy images, showing homogenous dispersion of SWNT in the PA6 phase. Differential scanning calorimetry results showed a slightly reduced percentage of crystallinity in samples containing SWNT. The mechanical properties of nanocomposites indicated an enhancement in tensile strength, modulus, and hardness on increasing SWNT content. J. VINYL ADDIT. TECHNOL., 22:336–341, 2016. © 2014 Society of Plastics Engineers