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ACS树脂的合成及性能研究 总被引:5,自引:0,他引:5
以氯化聚乙烯(CPE),苯乙烯(St)和丙烯腈(AN)为原料合成了接枝型ACS树脂,研究了合成的影响因素和产物的流变性及力学性能。 相似文献
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《国际聚合物材料杂志》2012,61(4):447-459
Abstract MCS resin, formed from methyl methacrylate (MMA), styrene (St), chlorinated polyethylene (CPE), was synthesized by suspension swelling graft-copolymerization. In this paper, the synthesis conditions of MCS, the effect of different synthesis conditions on graft efficiency, the mechanical properties, rheological behavior and morphology were investigated. The graft efficiency increased with increasing CPE content. The apparent viscosity of melt increased with increasing the content of CPE. The copolymer composition was analyzed by FTS-40 Fourier transform infrared spectrometer and PE-2400 element analyzer. The fractured surface morphology of MCS resin was observed by SEM and X-ray energy dispersive spectroscopy. 相似文献
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The rheological and rheo-optical properties of solutions of high molecular weight polyvinylalcohol (PVA) with different syndiotactic diad contents in dimethylsulfoxide (DMSO) were investigated in terms of tacticity, molecular weight, and degree of saponification. Tacticity played a significant role in rheological behavior. Over the frequency range of 10?1 to 102 rad/s PVA with syndiotactic diad content of ~53% (atactic PVA) exhibited almost Newtonian flow behavior whereas PVA with syndiotactic diad content of ~63% (syndiotactic PVA) exhibited Bingham flow behavior. On the plot of storage modulus (G′) against loss modulus (G″) atactic PVA gave slopes of ~2 while syndiotactic PVA gave slopes of ~1. With syndiotactic PVA, an increase of shear rate notably increased flow birefringence (Δnf) at shear rates higher than 5 sec?1. On the other hand, only a slight increase in Δnf was observed in the case of atactic PVA. The effects of molecular weight and degree of saponification were discussed as well. 相似文献
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Poly(vinyl chloride)/chlorinated polyethylene (PVC/CPE)/methylacryloylpropyl‐containing polyhedral oligomeric silsesquioxane (MAP–POSS) nanocomposites are prepared. The plastic behavior and dynamic rheological behavior of PVC/CPE/MAP–POSS are investigated. The influences of composition on dynamic storage modulus G′, loss modulus G″, and complex viscosity η* of PVC/CPE/MAP–POSS melts are discussed. The dynamic mechanical properties, mechanical properties, and morphology are determined. The results show that both plastic time and balance torque of the nanocomposites decrease, but the G′, G″, and η* all increase with increasing MAP–POSS content. The maximum value of the dynamic mechanical loss tan δ decreases and elasticity increases when MAP–POSS is added. The impact strength of the nanocomposites increases with increasing MAP–POSS content and has the best value at 10% content of MAP–POSS, which is 5.38 kJ/m2 higher than that of the blend without MAP–POSS. The MAP–POSS can be used as an efficient process aid and impact aid for the PVC/CPE blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Toughening modification of (Acrylonitrile‐styrene‐acrylic copolymer)/(α‐Methylstyrene‐acrylonitrile copolymer) binary blend via using different impact modifiers 下载免费PDF全文
In this work, different impact modifiers such as acrylic resin impact modifier, chlorinated polyethylene (CPE), nitrile rubber, powdered nitrile rubber, and hydrogenated nitrile rubber, were chosen to improve the toughness of (acrylonitrile‐styrene‐acrylic copolymer)/(α‐methylstyrene‐acrylonitrile copolymer) (ASA/α‐MSAN) binary blend. The blend ratios of the ASA/(α‐MSAN)/(impact modifier) ternary system were 30/70/20 and 70/30/20 by mass, respectively. The results showed that the impact strength significantly increased, nearly 30 times (22.59 kJ·m?2, 22.26 kJ·m?2, and 25.24 kJ·m?2) compared with that of control samples (0.80 kJ·m?2) when nitrile rubber, powdered nitrile rubber, or hydrogenated nitrile rubber was added to the ASA/(α‐MSAN) (30/70) matrix, respectively. Moreover, the impact strength of ASA/(α‐MSAN) (70/30) was dramatically enhanced to 46 kJ·m?2 with the addition of 20 parts by weight per hundred parts of resin of chlorinated polyethylene. The toughness of ASA/(α‐MSAN) with or without impact modifiers was also characterized via fracture energy calculated from stress‐strain curves. The results were perfectly consistent with that of impact strength. The results of dynamic mechanical analysis demonstrated the existence of α‐MSAN (glass transition temperature at approximately 140°C). The heat distortion temperature was barely changed, indicating the addition of impact modifiers barely affects the heat resistance. J. VINYL ADDIT. TECHNOL., 22:326–335, 2016. © 2014 Society of Plastics Engineers 相似文献
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新型ACS树脂综合性能的研究 总被引:1,自引:0,他引:1
本文主要研究了新型ACS树脂的流动性、力学性能、热性能、耐老化性能以及阻燃性能,并与ABS、AAS树脂进行了性能对比。结果表明:随着CPE含量的增加,ACS树脂的抗冲击性和阻燃性提高,熔体流动速率、拉伸强度、断裂强度和热变形温度都下降;并且ACS的抗冲击性能、耐候性和阻燃性远远高于ABS和AAS树脂。 相似文献
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研究了氯乙烯悬浮聚合时添加氯化聚乙烯(CPE)冲击改性剂、CaCO3填料、润滑剂及热稳定剂对聚合反应的影响,并对得到的可直接加工的原位聚合聚氯乙烯(RTUPVC)树脂的性能进行了表征。结果发现:CPE和CaCO3的加入均使达到相同压降的聚合时间缩短,氯乙烯聚合转化率相应减小;RTUPVC树脂的粒径随CPE粒径和用量的增大而增大,而CaCO3含量对RTUPVC树脂粒径影响不大;润滑剂和热稳定剂的加入,对聚合反应起延缓作用,但对RTUPVC树脂粒径影响不大;RTUPVC树脂加工塑化时间随CPE含量的增加而减少;相同CPE用量时,RTUPVC树脂的冲击强度和拉伸强度明显高于PVC/CPE共混物。 相似文献
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The extensional rheological properties of three grades of polyethylene melts, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE) were measured using a melt spinning technique under the test conditions with temperature ranging from 150 to 210°C and extrusion rate varying from 11.25 to 22.50 mm s?1. The results showed that the melt strength decreased with a rise of temperature while increased with an increase of extensional rate. With the rise of extensional strain rate and temperature, the melt extensional viscosity decreased. The extensional stress and viscosity reduced with increasing extrusion velocity when the temperature and extensional rate were constant. Moreover, the melt strength and extensional viscosity of the LDPE resin was the highest and the LLDPE was the lowest under the same experimental conditions. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers 相似文献
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The effect of Na‐alginate content on the gas permeation properties of water‐swollen membranes prepared by varying Na‐alginate and poly(vinyl alcohol) (PVA) content in membranes was investigated. The influences of water content and crystallinity of the membranes on the gas permeation performance of the water‐swollen membranes were studied. The gas permeation rate and selectivity of Na‐alginate/PVA water‐swollen membranes were compared with those of the dry membranes. The permeation rates of nitrogen and carbon dioxide through water‐swollen membranes were in the range of 0.4–7.6 × 10?7 to 3.7–8.5 × 10?6 cm3 (STP)/cm2 s?1 cmHg?1, which were 10,000 times higher than those of dry‐state membranes. The permeation rates of mixture gases through water‐swollen Na‐alginate/PVA membranes were found to increase exponentially with the increase of Na‐alginate content, whereas carbon dioxide concentration in permeates was decreased linearly. It was found that the gas permeance of the water‐swollen membranes increased with increasing the Na‐alginate content in the membrane. Gas permeation rates of the water‐swollen Na‐alginate/PVA membranes increased with increasing the water content in the membrane and decreasing the crystallinity of the membrane. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3225–3232, 2004 相似文献
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The effect of the molecular weight and acrylonitrile (AN) content of the styrene-acylonitrile copolymer (SAN) on the morphology, mechanical, and rheological properties of SAN/chlorinated polyethylene (CPE) blends was studied. The interaction between dispersed particle and matrix is expected to be optimal at the 25% AN content of SAN. Phase inversion from a dispersion to a continuous phase appears to occur above 50 wt % CPE. Mechanical properties increased with molecular weight at a constant AN content of SAN. Morphological, mechanical, and rheological properties were more sensitive to the AN content, rather than the molecular weight of SAN. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 27–36, 1998 相似文献
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Preparation and characterization of LDPE/PVA blend films filled with glycerin‐plasticized polyvinyl alcohol 下载免费PDF全文
A series of LDPE/PVA blend films were prepared via a twin‐screw extruder, and their morphology, thermal property, oxygen and water vapor permeation, surface properties, and mechanical properties were investigated as a function of the PVA content. During the extrusion process of the blend films, glycerin improved the compatibility and processing conditions between LDPE and PVA. The melting temperature (Tm), melting enthalpy (ΔHm), crystallinity (%), and thermal stability of the thermal decomposition temperature (T5%) of the LDPE/PVA blend films decreased with increasing PVA content. The oxygen permeabilities of the blend films decreased from 24.0 to 11.4 cm3·cm (m2·day·atm)?1 at 23°C. The WVTR increased from 7.8 to 15.0 g(m2 day)?1 and the water uptake increased from 0.13 to 9.31%, respectively. The mechanical properties of blend films were slightly enhanced up to 2% PVA and then decreased. The physical properties of the blend films strongly varied with the chemical structure and morphology depending on the PVA and glycerin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41985. 相似文献
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Blends of poly(vinyl chloride) (PVC) and acrylonitrile-chlorinated polyethylene-styrene (ACS) graft copolymer were prepared by melt blending. Mechanical properties were studied by the use of dynamic mechanical analysis (DMA), impact tests, tensile tests, and scanning electron microscopy (SEM). The DMA study showed that PVC is immiscible with chlorinated polyethylene in ACS but partially miscible with poly(styrene-co-acrylonitrile) (25% acrylonitrile content) in ACS. Mechanical property tests showed that there is a significant increase in the impact strength while other good mechanical properties of PVC such as high modulus and high strength remain. SEM observations supported the results of the mechanical properties studies. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 399–405, 1997 相似文献
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Enhanced oxygen‐barrier and water‐resistance properties of poly(vinyl alcohol) blended with poly(acrylic acid) for packaging applications 下载免费PDF全文
To enhance the oxygen‐barrier and water‐resistance properties of poly(vinyl alcohol) (PVA) and expand its food packaging applicability, five crosslinked poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) blend films were prepared via esterification reactions between hydroxyl groups in PVA and carboxylic acid groups in PAA. The physical characteristics of the blends, including the thermal, barrier, mechanical and optical properties, were investigated as a function of PAA ratio. With increasing PAA content, the crosslinking density was significantly increased, resulting in changes in the chemical structure, morphology and crystallinity of the films. The oxygen transmission rate of pure PVA decreased from 5.91 to 1.59 cc m?1 day?1 with increasing PAA ratio. The water resistance, too, increased remarkably. All the blend films showed good optical transparency. The physical properties of the blend films were strongly correlated with the chemical structure and morphology changes, which varied with the PAA content. © 2016 Society of Chemical Industry 相似文献
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The rubber particles included in rubber modified polymeric materials such as acrylonitrile‐butadiene‐styrene (ABS) polymer and impact modified polymers play an important role in determining their rheological properties, processing behavior, and mechanical properties. In this study both small strain oscillatory shear viscosity in the frequency range from 10?2 to 102 s?1 and uniaxial elongational viscosity behavior at two elongation rates ( = 0.1 and 1.0 s?1) over the range of temperatures from 140°C to 200°C were measured for commercial ABS polymers with different contents and deformability of rubber particles. The influences of rubber content and deformability on rheological properties such as melt elasticity, elongational viscosity, strain hardening and/or softening, the onset of nonuniform deformation, and thermoforming performance were investigated. The Wagner two‐parameter nonlinear viscoelastic constitutive model was used to describe strain hardening behavior, while the Considère criterion was used to determine the onset point of nonuniform deformation. The part thickness distribution obtained through use of a vacuum snap‐back forming process was simulated to investigate the effects of rheological changes associated with different rubber particles on the thermoforming performance. It was found that ABS polymers with larger contents of hard rubber particles exhibited more melt elasticity, stronger strain hardening, a maximum of biaxial elongational viscosity, onset of nonuniform deformation at later time, and better thermoforming performance. Strain hardening and the Considère criterion provide simple, reliable indicators of the thermoforming performance of ABS polymers. 相似文献
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Yasuo Ohta Hiroki Murase Hiroshige Sugiyama Hiroshi Yasuda 《Polymer Engineering and Science》2000,40(11):2414-2422
The rheological properties of a semi‐dilute ultra‐high molecular weight polyethylene (UHMw‐PE)/paraffin wax solution were investigated by mainly focusing on the influence of its concentration on the shear flow viscosity. It was found that the UHMw‐PE solution exhibits a shear‐thinning behavior at a very wide shear rate range from 10?4 to higher than 103 sec?1. Furthermore, this typical non‐Newtonian behavior was more obvious with a concentration increase. From the concentration dependence of the zero‐shear creep compliance or other rheological factor, it was found that the extremely large Me value of the system gives rise to various kinds of non‐Newtonian behaviors, especially those highly elastic in nature. Finally, the origin of the abnormal stress fluctuation during the steady shear measurement was found to be related to the shear‐induced structural development of the solution. 相似文献
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Sam Soo Kim In Seok Seo Jeong Hyun Yeum Byung Chul Ji Joon Ho Kim Jin Woo Kwak Won Sik Yoon Seok Kyun Noh Won Seok Lyoo 《应用聚合物科学杂志》2004,92(3):1426-1431
To precisely identify the effect of the molecular weight of syndiotacticity‐rich poly(vinyl alcohol) (s‐PVA) on the rheological properties of s‐PVA/water solutions, we prepared four s‐PVAs with a syndiotactic dyad content of 57%, a degree of saponification (DS) of 99.9%, and number‐average degrees of polymerization (Pn's) of 300, 1300, 2700, and 4000. Through a series of experiments, we found that the molecular weight of poly(vinyl alcohol) had a significant influence on the rheological properties of s‐PVA/water solutions. Over a frequency range of 10?1 to 102 rad/s, the s‐PVA/water solution with the highest Pn value showed the largest values of the complex viscosity, storage modulus, and loss modulus at similar syndiotacticity and DS values of s‐PVA, and this suggested that the higher Pn was, the stronger the internal ordered structure was in the molecules. All the s‐PVA/water solutions showed shear‐thinning behavior, which implied heterogeneity. In a modified Casson plot, Bingham flow behaviors, which gave rise to non‐zero yield stress, were evident. This suggested that some pseudostructure existed in the s‐PVA/water solutions. The yield stress increased with Pn, and this implied that the pseudostructure was developed as Pn increased. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1426–1431, 2004 相似文献