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1.
A series of poly(acrylonitrile‐butadiene‐styrene) (ABS) grafting modifiers were synthesized by emulsion grafting poly(acrylonitrile‐styrene) (SAN) copolymer onto polybutadiene (PB) latex rubber particles. The chain transfer reagent tert‐dodecyl mercaptan (TDDM) was used to regulate the grafting degree of ABS and the molecular weight of SAN copolymers. By blending these ABS modifiers with Chlorinated polyvinyl chloride (CPVC) resin, a series of CPVC/ABS blends were obtained. The morphology, compatibility, and the mechanical properties of CPVC/ABS blends were investigated. The scanning electron microscope (SEM) studies showed that the ABS domain all uniformly dispersed in CPVC matrix. Dynamic mechanical analyses (DMA) results showed that the compatibility between CPVC and SAN became enhanced with the TDDM content. From the mechanical properties study of the CPVC/ABS blends, it was revealed that the impact strength first increases and then decreases with the TDDM content, which means that the compatibility between CPVC and the SAN was not the only requirement for maximizing toughness. The decreasing of tensile strength and the elongations might attribute to the lower entanglement between chains of CPVC and SAN. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers  相似文献   

2.
Tetramethylpolycarbonate‐block‐poly(styrene‐co‐acrylonitrile) (TMPC‐block‐SAN) block copolymers containing various amounts of acrylonitrile (AN) were examined as compatibilizers for blends of polycarbonate (PC) with poly(styrene‐co‐acrylonitrile) (SAN) copolymers. To explore the effects of block copolymers on the compatibility of PC/SAN blends, the average diameter of the dispersed particles in the blend was measured with an image analyzer, and the interfacial properties of the blends were analyzed with an imbedded fibre retraction technique and an asymmetric double‐cantilever beam fracture test. Reduction in the average diameter of dispersed particles and effective improvement in the interfacial properties was observed by adding TMPC‐block‐SAN copolymers as compatibilizer of PC/SAN blend. TMPC‐block‐SAN copolymer was effective as a compatibilizer when the difference in the AN content of SAN copolymer and that of SAN block in TMPC‐block‐SAN copolymer was less than about 10 wt%. Copyright © 2004 Society of Chemical Industry  相似文献   

3.
王硕  刘哲  盛光  吕洁  郭阳  李刚 《弹性体》2010,20(1):46-52
采用种子乳液聚合技术在聚丁二烯(PB)乳胶粒子上接枝共聚苯乙烯(St)、α-甲基苯乙烯(α—MSt)和丙烯腈(AN)单体,合成了一系列不同AN结合量的ABS和α—MABS接枝共聚物。将其与聚氯乙烯(PVC)树脂熔融共混制得了PVC/AtkS共混物,利用扫描电镜(SEM)、透射电镜(TEM)和动态力学分析仪(DMA)对共混物的相容性和相结构进行了表征。结果发现,在PVC/ABS共混体系中,尽管改变接枝SAN共聚物的AN结合量,PVC和ABS接枝共聚物均为不相容体系;在ABS接枝共聚物中引入α-MSt后,当接枝SAN共聚物的AN结合量为18.7%~23.6%(质量分数)时,共混物在室温以上只存在1个tanδ峰,共混物成为相容体系,当AN结合量达到32.1%(质量分数)时,共混物成为部分相容体系。共混物的相区尺寸明显地依赖于接枝SAN共聚物中的AN结合量,与动态力学性能结果表现出良好的吻合。  相似文献   

4.
Block copolymers of polycarbonate (PC) and polymethylmethacrylate (PMMA), PCb‐PMMA, were examined as compatibilizers for blends of PC with styrene‐co‐acrylonitrile (SAN) copolymer. PC‐b‐PMMA was added to blends of PC with SAN containing various amounts of AN. The average diameter of the dispersed particles was measured with an image analyzer, and the interfacial properties of the blends were analyzed with an imbedded fiber retraction (IFR) test and an asymmetric double cantilever beam fracture test. The average particle size and interfacial tension of the PC/SAN blends reached a minimum value when the SAN copolymer contained about 24 wt% AN. A maximum in the adhesion energy was also observed at the same AN content. Interfacial tension and particle size were further reduced by adding PC‐b‐PMMA to the PC/SAN blends. Fracture toughness of the blends was also improved by enhancing the interfacial adhesion by the addition of PC‐b‐PMMA. The addition of PC‐b‐PMMA copolymer was more effective at improving the interfacial properties of PC/SAN blends than was varying the AN content of the SAN copolymers. The interfacial properties of the PC/SAN blends were optimized by adding a block copolymer and using an SAN copolymer that had minimum interaction energy with PC.  相似文献   

5.
The miscibility was investigated in blends of poly(methyl methacrylate) (PMMA) and styrene‐acrylonitrile (SAN) copolymers with different acrylonitrile (AN) contents. The 50/50 wt % blends of PMMA with the SAN copolymers containing 5, 35, and 50 wt % of AN were immiscible, while the blend with copolymer containing 25 wt % of AN was miscible. The morphologies of PMMA/SAN blends were characterized by virtue of scanning electron microscopy and transmission electron microscopy. It was found that the miscibility of PMMA/SAN blends were in consistence with the morphologies observed. Moreover, the different morphologies in blends of PMMA and SAN were also observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

6.
Poly(butyl acrylate) grafted styrene and acrylonitrile copolymer (PBA-g-SAN, ASA) with core–shell structures were prepared by emulsion polymerization technology to improve the toughness of the poly(vinyl chloride) (PVC). The mechanical properties of the PVC/ASA blends were investigated. The notch impact strength of the PVC/ASA blend could reach 1200 J/m when the 13 phr ASA was added to the PVC. This was several times more than pure PVC resin. Scanning electron microscopy analysis results indicated that the improvement in impact strength of the PVC/ASA blend was attributed to shear yielding induced by ASA particles. Additionally, subtle changes in the ratio of monomers in the shell layer led to significant fluctuations in the mechanical properties of the composites. Dynamic mechanical analysis showed that the intermolecular interaction forces between ASA particles and PVC resins played a key role in improving the toughness of PVC/ASA blend.  相似文献   

7.
采用悬浮聚合法,以丙烯酸丁酯、苯乙烯和丙烯腈为原料,合成了一系列丙烯酸丁酯-苯乙烯-丙烯腈(ASA)树脂。考察了橡胶相聚丙烯酸丁酯(PBA)、甲基丙烯酸烯丙酯(ALMA)和叔十二碳硫醇(TDDM)用量对ASA树脂的力学性能影响。结果表明:PBA质量分数达到20%后,ASA树脂的冲击强度大幅增加。TDDM的加入使苯乙烯-丙烯腈(SAN)的相对分子质量降低,当其质量分数低于1%时,ASA树脂的冲击强度呈升高趋势,质量分数高于1%时其冲击强度大幅降低。随PBA含量增加,ASA树脂的拉伸强度减小,断裂伸长率变大。  相似文献   

8.
A novel rigid poly(vinyl chloride) (PVC)/acrylonitrile–styrene–acrylate (ASA) copolymer blend with good ultraviolet (UV) irradiation resistance and toughness was reported. ASA with good weatherability and toughness was mixed with PVC by conical twin‐screw extruder to improve the UV irradiation resistance and toughness of PVC. The blends were characterized using Fourier‐transform infrared spectra, dynamic mechanical analysis, and scanning electron microscope. Notch Charpy impact test was used to characterize the UV radiation induced changes in toughness. The results showed that ASA was able to toughen PVC with simultaneously improving heat resistance, thermal stabilization, and protecting PVC from irradiation photochemical degradation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2143–2151, 2013  相似文献   

9.
The effects of different acrylic rubber (PBA) contents in core‐shell structured rubbery acrylate‐g‐poly (styrene‐acrylonitrile) (PBA‐SAN) on the mechanical properties of PBA‐SAN and PBA‐SAN/SAN blends were systematically investigated. Fourier transform‐infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to characterize the structure and morphology of PBA‐SAN and PBA‐SAN/SAN blends, respectively. It was found that the mechanical properties of PBA‐SAN and PBA‐SAN/SAN blends strongly depended on the PBA content: largely improved impact strength and elongation at break were observed when adding PBA‐SAN with high PBA content. However, the loss in rigidity and heat distortion temperature were accompanied. Specifically, both PBA‐SAN and PBA‐SAN/SAN blends with 60 wt% PBA exhibited a good balance between toughness and rigidity, which indicating PBA‐SAN with 60 wt% PBA was the most suitable impact modifier. J. VINYL ADDIT. TECHNOL., 24:262–267, 2018. © 2016 Society of Plastics Engineers  相似文献   

10.
Miscibility, phase diagrams and morphology of poly(ε‐caprolactone) (PCL)/poly(benzyl methacrylate) (PBzMA)/poly(styrene‐co‐acrylonitrile) (SAN) ternary blends were investigated by differential scanning calorimetry (DSC), optical microscopy (OM), and scanning electron microscopy (SEM). The miscibility window of PCL/PBzMA/SAN ternary blends is influenced by the acrylonitrile (AN) content in the SAN copolymers. At ambient temperature, the ternary polymer blend is completely miscible within a closed‐loop miscibility window. DSC showed only one glass transition temperature (Tg) for PCL/PBzMA/SAN‐17 and PCL/PBzMA/SAN‐25 ternary blends; furthermore, OM and SEM results showed that PCL/PBzMA/SAN‐17 and PCL/PBzMA/SAN‐25 were homogeneous for any composition of the ternary phase diagram. Hence, it demonstrated that miscibility exists for PCL/PBzMA/SAN‐17 and PCL/PBzMA/SAN‐25 ternary blends, but that the ternary system becomes phase‐separated outside these AN contents. Copyright © 2003 Society of Chemical Industry  相似文献   

11.
This study attempted to correlate morphological changes and physical properties for a high rubber content acrylonitrile–butadiene–styrene (ABS) and its diluted blends with a poly(styrene‐co‐acrylonitrile) (SAN) copolymer. The results showed a close relationship between rubber content and fracture toughness for the blends. The change of morphology in ABS/SAN blends explains in part some deviations in fracture behavior observed in ductile–brittle transition temperature shifts. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2606–2611, 2004  相似文献   

12.
We investigated the miscibility windows in the blends of poly(vinyl chloride) (PVC) with chemically modified styrene/acrylonitrile (SAN) copolymers such as α-methyl styrene/acrylonitrile (α SAN), α-methyl styrene/methacrylonitrile (MSMAN). The blends of PVC with α SAN were found to have the broader miscibility window. This enhanced miscibility was interpreted in terms of intramolecular repulsion that originates from unfavorable interaction between counits of the copolymers and also intramolecular association of AN units. The intramolecular interactions were studied by using Fourier transform infrared (FT-IR) spectroscopy. These interactions were reflected by a peak broadening in the nitrile stretching band in the acrylonitrile segments. The intermolecular interactions governing the miscibility in the blends of PVC with the series of copolymers were also discussed.  相似文献   

13.
A series of methyl methacrylate‐butadiene‐styrene (MBS) graft copolymers were synthesized via seeded emulsion polymerization techniques by grafting styrene and methyl methacrylate on poly(butadiene‐co‐styrene) (SBR) particles. The chlorinated poly(vinyl chloride) (CPVC)/MBS blends were obtained by melting MBS graft copolymers with CPVC resin, and the effect of the core/shell ratio of MBS graft copolymer and SBR content of CPVC/MBS blends on the mechanical properties and morphology of CPVC/MBS blends was studied. The results showed that, with the increase in the core/shell ratio, the impact strength of the blend increased and then decreased. It was found that, when the core/shell ratio was 50/50, the impact strength was about 155 J/m, and the tensile strength evidently increased. The toughness of the CPVC/MBS blend was closely related to the SBR content of the blend, and with the increasing of SBR content of blend, the impact strength of the blend increased. The morphology of CPVC/MBS blends was observed via scanning electron microscopy. Scanning electron microscopy indicated that the toughness of CPVC/MBS blend was consistence with the dispersion of MBS graft copolymers in the CPVC matrix. J. VINYL ADDIT. TECHNOL., 22:501–505, 2016. © 2015 Society of Plastics Engineers  相似文献   

14.
A series of α-methylstyrene, styrene, and acrylonitrile (α-MSAN) copolymers with different acrylonitrile (AN) contents were synthesized by altering α-MSt, St, and AN ratios with emulsion copolymerization method. By melt-blending these copolymers with PVC resin and di-isooctyl phthalate (DOP), PVC/α-MSAN, and PVC/α-MSAN/DOP blends were prepared. The miscibility and morphology of the blends were investigated by dynamic mechanical analysis (DMA) and scanning electron microscopy. The PVC is immiscible with SAN by melt-mixing, whereas PVC is miscible with α-MSAN (α-MSt/St = 1/1) if AN weight percent is within the window range of 20–25 wt %, and α-MSAN (not containing St) with 35 wt % AN is miscible with PVC even when they are blended by melt-mixing. Replacement of styrene with α-methylstyrene widens the miscibility window with PVC. The miscibility of PVC/α-MSAN blends is substantially improved with the increasing α-MSt content in α-MSAN copolymer containing identical AN content. When DOP was introduced into the PVC/α-MSAN (α-MSt/St = 1/1) blends, a single tan δ peak over room temperature in DMA detection is found as AN content in α-MSAN copolymer is within the range of 15–25 wt %, and SEM observation also shows that the blends are homogeneous. When the AN content in α-MSAN copolymer is over 35 wt %, the presence of DOP causes the phase domain extended. The phase domain size of the PVC/α-MSAN/DOP blends intensively depends on AN content in α-MSAN copolymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

15.
Abstract

Nitrile–butadiene rubbers (NBRs) with different acrylonitrile (AN) contents were used to toughen acrylonitrile–styrene–acrylic terpolymer/styrene–acrylonitrile copolymer (ASA/SAN) blends. The properties of the ASA/SAN/NBR ternary blends were investigated via dynamic mechanical analysis, heat distortion temperature, Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). The effects of AN content in NBR on physical properties, heat resistance and morphology of the ternary blends were studied. Heat distortion temperature of the blends decreased with increasing AN content of NBR. The impact strength reached the maximum value when 20 phr NBR with 26 wt-%AN content was added. Images (SEM) were in accordance with results of mechanical properties.  相似文献   

16.
《Polymer》1995,36(6):1269-1273
The core—shell graft copolymer of α-methyl styrene with acrylonitrile on poly(butyl acrylate) was synthesized. The graft polymerization was investigated as a function of reaction temperature, initiator concentration used in the secondary polymerization, monomer to polymer ratio and emulsifier concentration. The compatibility of this core—shell graft copolymer with poly(vinyl chloride) (PVC) was determined by the solubility parameter method and scanning electron microscopy. The mechanical and rheological behaviour of the blend show that this core—shell graft copolymer can be used as a processing aid for PVC.  相似文献   

17.
The performance of acrylonitrile–butadiene–styrene (ABS) core–shell modifier with different grafting degree, acrylonitrile (AN) content, and core–shell ratio in toughening of poly(butylene terephthalate) (PBT) matrix was investigated. Results show PBT/ABS blends fracture in ductile mode when the grafting degree is high, and with the decrease of grafting degree PBT/ABS blends fracture in a brittle way. The surface of rubber particles cannot be covered perfectly for ABS with low grafting degree and agglomeration will take place; on the other hand, the entanglement density between SAN and PBT matrix decreases because of the low grafting degree, inducing poor interfacial adhesion. The compatibility between PBT and ABS results from the strong interaction between PBT and SAN copolymer and the interaction is influenced by AN content. Results show ABS cannot disperse in PBT matrix uniformly when AN content is zero and PBT/ABS fractures in a brittle way. With the addition of AN in ABS, PBT/ABS blends fracture in ductile mode. The core–shell ratio of ABS copolymers has important effect on PBT/ABS blends. When the core–shell ratio is higher than 60/40 or lower than 50/50, agglomeration or cocontinuous structure occurs and PBT/ABS blends display lower impact strength. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 5363–5371, 2006  相似文献   

18.
The morphology and mechanical properties of polycarbonate (PC) blends with rubber‐toughened styrene–maleic anhydride copolymer materials (TSMA) were investigated and compared with the properties of blends of PC with acrylonitrile–butadiene–styrene (ABS) materials. The PC/TSMA blends showed similar composition dependence of properties as the comparable PC/ABS blends. Polycarbonate blends with TSMA exhibited higher notched Izod impact toughness than pure PC under sharp‐notched conditions but the improvements are somewhat less than observed for similar blends with ABS. Since PC is known for its impact toughness except under sharp‐notched conditions, this represents a significant advantage of the rubber‐modified blends. PC blends with styrene–maleic anhydride copolymer (SMA) were compared to those with a styrene–acrylonitrile copolymer (SAN). The trends in blend morphology and mechanical properties were found to be qualitatively similar for the two types of copolymers. PC/SMA blends are nearly transparent or slightly pearlescent. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1508–1515, 1999  相似文献   

19.
Styrene‐acrylonitrile random copolymer (SAN) and polyarylate (PAr) block copolymer were applied as a reactive compatibilizer for polyamide‐6 (PA‐6)/acrylonitrile‐butadiene‐styrene (ABS) copolymer blends. The SAN–PAr block copolymer was found to be effective for compatibilization of PA‐6/ABS blends. With the addition of 3.0–5.0 wt % SAN–PAr block copolymer, the ABS‐rich phase could be reduced to a smaller size than 1.0 μm in the 70/30 and 50/50 PA‐6/ABS blends, although it was several microns in the uncompatibilized blends. As a result, for the blends compatibilized with 3–5 wt % block copolymer the impact energy absorption reached the super toughness region in the 70/30 and 50/50 PA‐6/ABS compositions. The compatibilization mechanism of PA‐6/ABS by the SAN–PAr block copolymer was investigated by tetrahydrofuran extraction of the SAN–PAr block copolymer/PA‐6 blends and the model reactions between the block copolymer and low molecular weight compounds. The results of these experiments indicated that the SAN–PAr block copolymer reacted with the PA‐6 during the melt mixing process via an in situ transreaction between the ester units in the PAr chain and the terminal amine in the PA‐6. As a result, SAN–PAr/PA‐6 block copolymers were generated during the melt mixing process. The SAN–PAr block copolymer was supposed to compatibilize the PA‐6 and ABS blend by anchoring the PAr/PA‐6 and SAN chains to the PA‐6 and ABS phases, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2300–2313, 2002  相似文献   

20.
A series of imidized acrylic polymers of varying structural composition generated by reaction of methylamine with poly(methyl methacrylate) were blended with a range of styrene/acrylonitrile or SAN copolymers (0–33% AN) and with poly(vinyl chloride). On the basis of glass transition behavior determined by differential scanning calorimetry, some but not all imidized acrylic structures were found to be miscible with PVC and with SAN copolymers within a limited window of AN levels. Acid functionality in the imidized acrylics appears to hinder their miscibility with SAN rather significantly and with PVC to a lesser extent. Miscible SAN blends showed lower critical solution temperature behavior whereas miscible blends with PVC did not up to the highest attainable temperatures. The composition factors that influence the phase behavior are described and interpreted in terms of possible mechanisms.  相似文献   

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