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1.
本文用傅里叶交换红外光谱法(FTIR)表征了苯乙烯-甲基丙烯酸共聚物P(S-MAA)和聚环氧丙烷(PPrO)共混体系的相容性.用谱带分离的技术比较准确地测定了共混体系中几种羰基的吸光系数比,并且用简明的方法定量计算了它们之间平衡的平衡常数.同时实验还表明共混组分中聚醚的分子量、分子结构、P(S-MAA)中MAA的含量以及共混组分的比例和体系的相容性有密切的关系.  相似文献   

2.
潘雁  黄玉惠 《应用化学》1997,14(2):53-56
用DSC、DMA研究了羧化聚苯醚(CPPO)/聚(苯乙烯-乙烯吡啶)(PSVP)共混体系的相容性,结果表明,与CPPO/PS体系相比,乙烯吡啶基的引入大大提高了共混相容性.这主要是由于CPPO中的羧基与PSVP中的吡啶基之间通过质子转移形成的正负离子间的相互作用,推动了两组分分子的均匀混合.  相似文献   

3.
甲基丙烯酸甲酯 甲基丙烯酸共聚物(P(MMA MAA))与低分子量或高分子量梯形聚苯基硅倍半氧烷(PPSQ)的共混物经原位聚合法制成.用光学透明法、荧光光谱、DSC等技术研究了该共混体系的相容性及组分间的相互作用及结构转变.结果表明,当PPSQ含量较小时,由于PPSQ与P(MMA MAA)间存在着较强的氢键作用,该共混体系在一定配比下相容,且低分子量PPSQ与P(MMA MAA)间的相容性较好.当PPSQ的含量≤1%时,PPSQ的加入对该共混物的Tg影响不大,但其Tf随PPSQ含量增加而增大.此外,还测试了P(MMA MAA)/PPSQ原位共混物的硬度及冲击强度.  相似文献   

4.
采用DMA和TEM系统研究了聚丁二烯-聚甲基丙烯酸甲酯的嵌段共聚物(PBD-b-PMMA)与聚氯乙烯(PVC)共混体系的相容性问题。结果表明:PVC/PBD-b-PMMA共混体系具有部分相溶性。相容的程度与共混体系的组成、组分聚合物的分子量以及共聚物中PBD和PMMA嵌段的比例密切相关。  相似文献   

5.
PC/ABS及PC/ABS/PE-g-MAH共混体系相容性的研究   总被引:18,自引:1,他引:17  
研究了聚碳酸酯与ABS(PC/ABS)及PC/ABS与马来酸酐接枝聚乙烯共聚物(PC/ABS/PE-g-MAH)共混体系的力学性能和应力开裂性能。用DSC和SEM研究了共混体系的相容性。结果表明:ABS的加入能提高PC的冲击强度,ABS的含量及品种影响PC/ABS合金的力学性能,ABS能提高PC的耐溶剂应力开裂性能。PC/ABS/PE-g-MAH共混体系的力学性能和相容性优于PC/ABS共混体系,  相似文献   

6.
PSt-b-PEO增容PA6/PS共混体系的研究   总被引:1,自引:0,他引:1  
采用动态力学方法(DMA),形态学方法(SEM),研究了PSt b PEO存在下尼龙6(PA6)/聚苯乙烯(PS)共混体系的相容性.研究表明,PA6和PS的简单共混体系,分散相相畴尺寸大,相界面清晰,断裂面光滑,呈脆性断裂,相容性极差,属不相容体系.而加入少量PSt b PEO后分散相尺寸变小,界面层变厚,界面粘结力增强,表现出韧性特征.  相似文献   

7.
利用DSC、DMA、TEM和XPS对[PSF-PDMS-PHS]n/PSF共混物的相容性及表面组成进行了研究.结果表明,PDMS在共混物表面的富集与PSF均聚物和[PSF-PDMS-PHS]n中硬段的相容性有关;PDMS在相容的共混物体系表面的富集与对应的多嵌段共聚物组成基本相近;不相容共混物体系表面PDMS的富集程度相对较高,当共混物本体中有机硅含量从1%增至5%,表面层PDMS的含量迅速增加,可达到嵌段共聚物中PDMS的含量.  相似文献   

8.
采用二甲基硅氧烷-b-乙二醇嵌段共聚物(DMS-b-OE)对聚二甲基硅氧烷/聚氨酯(PDMS/PU)共混体系的增容,重点研究了增容共混体系的微观形态结构和软科学性能之间的关系。扫描电子显微镜、动态力学分析和力学性能测试结果表明:DMS-b-OE对PDMS/PU具有优良的增容作用,改善了PDMS/PU共混体系的相容性,提高了该共混物的力学性能。其抗张强度由3.4MPa提高到7.6MPa。  相似文献   

9.
用DSC,DMTA研究了醋酸纤维素(CDA),聚乙烯基吮咯烷酮(PVP)及CDA/PVP共混体系的玻璃化转变行为.用精密量热法测定了该体系的混合热焓.结果表明:共混体系只存在一个玻璃化转变温度(Tg),其值随共混组成的变化而改变;共混体系的混合热焓为负值,其绝对值随组成中PVP含量的增加而减少.力学性能研究表明,共混体系具有协同效应.上述试验结果证明,CDA和PVP是一对相容性高聚物.  相似文献   

10.
运用DSC物理老化和FTIR谱带分离及拟合技术,对聚氨酯(TPU)硬段模型聚合物(HM)和苯乙烯-丙烯腈共聚物(SAN)的共混体系进行了研究。实验结果表明,HM/SAN是一个相容体系,体系的相容性来源于两组分聚合物之间的特殊相互作用。SAN的加入消弱了HM中羰基和氨基间的氢键相互作用,这一结果对阐明TPU/SAN共混体系相容性本质提供了重要的依据。  相似文献   

11.
 Styrene-methacrylic acid copolymer (P(S-MAA)) nanoparticles having high Tg were produced by a dissolution of submicron-sized P(S-MAA) particles as follows. Submicron-sized P(S-MAA) particles having various MAA contents were produced by emulsion copolymerization. Secondly, they were treated in a polyoxyethylene nonylphenyl-ether nonionic emulsifier aqueous solution at pH 13.0 and above 90 °C. The nanoparticles having about 30 nm in diameter were only produced from the particles having MAA contents around 7 mol%, and above the contents, they were not produced. It seems to be based on that emulsifier molecules are not adsorbed onto the polymer molecules enough to dissolve them. The effect of MAA content on such a dissolution behavior was examined using seven kinds of different nonionic emulsifiers having hydrophile-lipophile-balance values between 12.2 and 18.2 at various temperatures and initial pH. Received: 12 June 1996 Accepted: 27 August 1996  相似文献   

12.
The adsorption behavior of poly(oxyethylene) nonyl phenyl ether nonionic emulsifier molecules onto polystyrene (PS) and styrene-methacrylic acid copolymer [P(S-MAA)] particles dispersed in D2O was evaluated by in situ 1H NMR measurements at room temperature. The resonance due to the protons of the emulsifier molecules was only observed. Normalized NMR integrals of the resonance due to the protons of hydrophobic groups (nonyl and phenyl groups) and the hydrophilic group, poly(oxyethylene) chain, at a certain concentration of the emulsifier decreased with an increase in the total surface area of the PS particles dispersed in the system. The decrease for the hydrophobic groups was much larger than that for the hydrophilic groups. In the dispersion system of P(S-MAA) particles, ionized carboxyl groups at the particle surface decreased the amount of the emulsifier adsorbed.  相似文献   

13.
The influence of nonionic emulsifier, included inside styrene-methacrylic acid copolymer [P(S-MAA)] particles during emulsion copolymerization, on the formation of multihollow structure inside the particles via the alkali/cooling method (proposed by the authors) was examined in comparison to emulsifier-free particles. It was clarified that the nonionic emulsifier included inside the P(S-MAA) particles eased the formation of multihollow structure.Part CCL of the series studies on suspension and emulsion  相似文献   

14.
通过开环共聚合,合成了3种不同单元比例的ε-己内酯(ε-CL)与L-丙交酯(L-LA)的共聚物P(CL-co-LA)。通过熔融共混制备了聚乳酸(PLA)/聚己内酯(PCL)/P(CL-co-LA)三元共混材料,研究了P(CL-co-LA)对共混材料微观形貌、热性能以及力学性能的影响。 结果表明,共聚物P(CL-co-LA)作为PLA/PCL不相容体系的界面增容剂,减小了PCL分散相的尺寸,改善了PLA/PCL共混体系的相容性,提高了共混材料的韧性。 固定m(PLA):m(PCL):m(P(CL-co-LA))=80:20:10时,以P(CL49/LA51)(其中数字代表摩尔分数(%))作为界面增容剂效果最佳,共混材料的断裂伸长率可达到(210±30)%。  相似文献   

15.
Miscibility of blends consisting of poly(vinyl methyl ether) (PVME) and poly(styreneco-2-vinylnaphthalene) [P(S-co-2VN)] was investigated by means of Fourier transform infrared (FT-IR) spectroscopy and thermal analysis. Copolymers containing 21, 51, and 84 wt % of styrene were synthesized by radical polymerization. Based on optical clarity and glass transition temperatures, it was shown that the miscibility in P(S-co-2VN)/PVME blends is largely affected by compositions of the copolymers as well as concentrations of the blend. From the FT-IR results, the relative intensity at 1100 cm?1 peak of COCH3 band of PVME and the position of naphthyl ring of 2VN were sensitive to the miscibility of the blends. It was observed that blends of PVME with P(S-co-2VN) of 84 wt % styrene or P(S-co-2VN) of 51 wt % styrene are miscible over the entire concentration ranges of the blends. Blends of PVME with P(S-co-2VN) containing 21 wt % of styrene are immiscible below 65 wt % PVME. In the miscible P(S-co-2VN)/PVME blends, there was observed a large shift in the naphthyl frequency at a characteristic wavelength of 748 cm?1. © 1993 John Wiley & Sons, Inc.  相似文献   

16.
We use Dip-Pen Nanolithography (DPN) to generate monolayer surface templates for guiding pattern formation in spin-coated polymer blend films. We study template-directed pattern formation in blends of polystyrene/poly(2-vinylpyridine) (PS/P2VP) as well as blends of PS and the semiconducting conjugated polymer poly(3-hexylthiophene) (P3HT). We show that acid-terminated monolayers can be used to template pattern formation in PS/P3HT blends, while hydrophobic monolayers can be used to template pattern formation in PS/P2VP blends. In both blends, the polymer patterns comprise laterally-phase separated regions surrounded by vertically separated bilayers. We hypothesize that the observed patterns are formed by template-induced dewetting of the bottom layer of a polymer bilayer during the spin-coating process. We compare the effects of template feature size and spacing on the resulting polymer patterns with predictions from published models of template-directed dewetting in thin films and find the data in good agreement. For both blends we observe that a minimum feature size is required to nucleate dewetting/phase separation. We find this minimum template diameter to be approximately 180 nm in 50/50 PS/P2VP blends, and approximately 100 nm in 50/50 PS/P3HT blends. For larger template diameters, PS/P2VP blends show evidence for pattern formation beginning at the template boundaries, while PS/P3HT blends rupture randomly across the template features.  相似文献   

17.
张涵  孙志强  庞烜  李帅  孙敬茹  陈文啟  陈学思 《应用化学》2015,32(11):1268-1274
通过开环聚合,合成不同比例的ε-己内酯(ε-CL)与L-丙交酯(L-LA)的无规共聚物P(CL/LLA)。 将上述共聚物P(CL/LLA)与聚乳酸(PLLA)共混,制备了PLA/P(CL/LLA)共混材料。 并对其相容性、热性能、力学性能进行了研究。 结果表明,共聚物P(CL/LLA)与PLA相容性与共聚物中LA单元含量和链段的平均长度有密切关系,P(CL/LLA)中LA链段平均长度达到3.4以上时,可以与PLA很好的相互作用。 同时共聚物P(CL/LLA)中-CL-链段有很好的柔性,可以很好的改善PLLA的韧性,使PLLA材料的断裂伸长率达到500%以上。  相似文献   

18.
The FT–IR spectroscopic analysis and the thermal behavior of the blends of styrene-1-vinyl naphthalene copolymers [P(S-co-1VN)] and poly(vinyl methyl ether) (PVME) were investigated in this work. The copolymers containing 23, 50, and 80% by weight of styrene were synthesized by radical polymerization. The blend films of the P(S-co-1VN) and PVME were cast from the mixed solvent of benzene/trimethylbenzene [50/50 (v/v)]. It was found from the optical clarity and the glass transition temperature behavior that the blends of PVME with P(S-co-1VN) of 80 wt % styrene and 20 wt % 1-vinylnaphthalene (1VN) show miscibility below 50 wt % of the copolymer concentration and the concentration range to show miscibility becomes wider as the composition of 1VN decreases in the copolymers. From the FT–IR results, the relative peak intensity of the 1100 cm?1 region due to COCH3 bond of PVME and the peak position of 774 cm?1 region due to the naphthyl ring of 1VN were sensitive to the miscibility of the P(S-co-1VN)/PVME blends. The frequency differences of the phenyl ring and the naphthyl ring in the P(S-co-1VN) from each frequency in the P(S-co-1VN)/PVME blends increase with increasing composition of styrene in the copolymers and with increasing concentration of PVME in the blends. A threshold energy exists to induce molecular interaction between the naphthyl ring of 1VN and the COCH3 of PVME and to result in the miscible blends, regardless of the copolymer composition as well as the blend concentration. The threshold energy was estimated as about 3.689 × 10?21 cal (779 cm?1) for the P(S-co-1VN)/PVME blend system. It can be concluded that the miscibility in P(S-co-1VN)/PVME blends is largely affected by the composition of the copolymers, and the blends become more miscible as the composition of styrene in the copolymers increases.  相似文献   

19.
With the objective of developing new biodegradable materials, the miscibility and the crystallinity of blends of poly(3-hydroxybutyrate), P(3HB), and poly(3-hydroxybutyrate-co-3-hydroxyvalerate), P(3HB-co-3HV), have been studied. P(3HB) (300 kg mol−1)/P(3HB-co-3HV)–10% 3HV (340 kg mol−1) blends were prepared by casting in a wide range of proportions, and characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). The experimental values for the glass transition temperatures (Tg) are in good agreement with the values provided by the Fox equation, showing that the blends are miscible. It was observed that the Tg and the melting temperature (Tm) decreases with the increase in the P(3HB-co-3HV)–10% 3HV content, while the crystallization temperature (Tc) increases. FT-IR analyses confirmed the decrease on the crystallinity of P(3HB)/P(3HB-co-3HV)–10% 3HV blends with higher copolymer contents. Bands related to the crystallinity were changed, due to the copolymer content that produced miscible and less crystalline blends.  相似文献   

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