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1.
通过熔融缩聚的方法,以己二酸、二元醇、甘油作为第三单体合成了含有支化结构的聚酯增塑剂,探究了不同二元醇合成的支化聚酯,并按照一定配方将聚酯加入到聚氯乙烯(PVC)中制得PVC试片,利用傅里叶红外光谱分析、热重分析、高效凝胶色谱分析对支化聚酯进行了表征,对PVC试片进行拉伸性能、热稳定性能、耐抽出性能等性能测试。结果表明,二元醇为二缩三乙二醇时,产品相对分子质量为4871,分散系数为2.26,黏度为11.20 Pa·s,支化聚酯增塑的PVC试片断裂伸长率高于400 %,吸水量低,热稳定性高,耐抽出性能良好。  相似文献   

2.
采用硅烷偶联剂(KH570)以及偶联剂和有机物(山梨醇、油酸、钛酸酯、聚乙二醇6000)复合对纳米二氧化钛(TiO_2)进行表面改性,研究了偶联剂和复合改性剂对纳米TiO_2抗紫外性能的影响。通过扫描电子显微镜、二次粒径分析、沉降试验、傅里叶变换红外光谱、同步热分析等对改性前后的纳米TiO_2进行表征。结果表明,KH570+聚乙二醇6000复合改性的纳米TiO_2二次粒径最小,平均粒径为0.047μm;沉降试验中其上清液在350 nm处的吸光度达最高为1.067 76;吸油值最大达86.19 cm~3/g,呈现良好的分散性和疏水性。另外,KH570+聚乙二醇6000改性的纳米TiO_2具有相对最强的紫外吸收能力,而且对亚甲基蓝溶液的降解率相对最小。将改性后的纳米TiO_2添加到PVC基体中,制得PVC/TiO_2薄膜,该薄膜经120 h加速老化后,发现由KH570+聚乙二醇6000改性纳米TiO_2制得的PVC薄膜的光透过率相对最低,拉伸性能最高,体现了其相对优越的抗紫外性能以及KH570+聚乙二醇6000相对优异的改性效果。  相似文献   

3.
This work reports tests performed to evaluate the stability of aqueous dispersions of inorganic oxide pigments with different specific surface areas, with the use of anionic and non-ionic surfactants and concentrators. Color mixtures of oxide compounds of blue, green, olive and brown with the unit cell spinel structure were used as pigments. The sodium salt of sulfosuccinic acid monoester, oxyethylenated nonylphenol and ethoxylated derivatives of lauryl alcohol, fatty alcohol and fatty amine were used as surfactants. The concentrators used were: poly(vinyl alcohol), the sodium salt of carboxymethyl cellulose as well as a water-based polyurethane oligomer. The highest dispersion efficiency was found for dispersed systems in which surfactant and concentrator were incorporated in the formula. The one containing the sodium salt of carboxymethyl cellulose or polyurethane oligomer with ethoxylated saturated fatty alcohol or fatty amine was found to be the most efficient. It was discovered that a higher dispersion efficiency corresponds to pigments with larger specific surface. The efficiency is also found to improve when the concentrator is an acrylic polymer or copolymer made up of two acrylic species. In this case, the concentrator interaction with the surfactant is more effective if the value of its boundary viscosity number is higher. This observation confirms the existence of interactions between macro-chains of the concentrator and surfactant molecules forming micelles with the pigment particles.  相似文献   

4.
以六亚甲基二异氰酸酯(HDI)和聚环氧丙烷醚二醇(PPG)为主要原料,二羟甲基丙酸(DMPA)为亲水性扩链剂合成了聚氨酯预聚体,再经过不同小分子扩链剂扩链、乳化制备水性聚氨酯(WPU)乳液,然后与自制交联剂HM交联成膜.研究了不同扩链剂对聚氨酯乳液稳定性及涂膜力学性能的影响.结果表明,以脂肪族二醇扩链的WPU乳液的外观好于芳香族二酚,而芳香族二酚扩链的WPU涂膜力学性能优于脂肪族二醇.  相似文献   

5.
加工助剂对PVC木塑复合材料性能的影响   总被引:2,自引:1,他引:1  
研究了4种新型加工助剂对聚氯乙烯(PVC)木塑复合材料的加工特性和物理力学性能的影响,并利用扫描电子显微镜(SEM)研究复合材料的冲击断面。结果表明,以不饱和芳香族碳氢化合物、脂肪烃树脂为主要组分的加工助剂,能够提高木粉在PVC基体中的分散性,改善木粉与PVC的相容性,从而明显提高PVC木塑材料的力学性能和加工性能;以钙皂和饱和脂肪酸酰胺混合物、脂肪醇和脂肪酸酯的混合物为主要组分的加工助剂,对木粉的分散性和复合材料的加工性能有一定的改善,但其用量较大时对复合材料的力学性能有不利影响。  相似文献   

6.
采用异佛尔酮二异氰酸酯和相对分子质量为6000的聚乙二醇为原料、十六醇为封端剂,合成了相对分子质量在10000~50000范围内的一系列两亲性脂肪族聚氨酯.用傅立叶变换红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、凝胶渗透色谱-光散射联用仪(GPC-LS)、高级旋转流变仪对两亲性聚氨酯的结构及其水分散液的流变性...  相似文献   

7.
柴飞 《中国氯碱》2003,(10):19-22
系统地分析了PVC树脂中杂质粒子的来源和产生原因,提出了解决的方法。杂质粒子与所用原材料、设备、工艺、聚合配方组分及氯乙烯单体中的铁化合物有关。在配方中全用聚乙烯醇做悬浮剂时由于反应前后浓度变化大而容易产生自聚物和粘釜物而增加杂质粒子,加入少量纤雏素可稳定悬浮剂浓度。单体含酸含水所产生的铁锈与氯化铁形成有色胶状物是杂质粒子的重要来源,采用在合成工段滴加碱溶液的方法消除酸和氯化铁,避免胶状物的产生。  相似文献   

8.
以二聚酸和乙二醇丁醚为原料,在催化剂钛酸四丁酯催化作用下,采用直接酯化法工艺合成了二聚酸二丁氧基乙酯。考察了原料配比、催化剂用量、带水剂用量、反应时间等因素对酯化反应的影响。结果表明:当乙二醇丁醚和二聚酸摩尔比为2.5∶1,钛酸四丁酯用量为二聚酸质量的1.0%,带水剂环己烷用量为二聚酸质量的17.5%,反应时间5h时,酯化率可达99.6%。建立了酯化反应表观动力学模型,反应速率方程为:r=9.2×105e-49.1/RTcA。通过FTIR和1H NMR对产物结构进行表征,并将二聚酸二丁氧基乙酯和DOP分别加入到PVC树脂中,通过溶剂铸膜法制成PVC塑料试片,对比其性能,二聚酸二丁氧基乙酯有良好的耐油、耐水抽出及热稳定性,可作为DOP的升级产品使用。  相似文献   

9.
实验表明,铸膜液浓度、PVC 分子量及其分布主要是通过它们对膜孔大小的影响来影响膜的性能。铸膜液浓度提高,膜孔缩小,截留率提高而透水率下降。这种影响在铸膜液百分浓度低于15%时尤为明显。分子量的均一则有利于膜孔的均一。聚乙二醇因其具有较多的羟基,当被添加到PVC/PAN 共混铸膜液中时,既起交联剂的作用,又起溶胀剂的作用,前者有利三维聚合物网络的形成而提高截留率,后者有利提高开放形孔所占的比例而增大透水率。  相似文献   

10.
磷钨酸铝催化合成缩醛(酮)   总被引:2,自引:1,他引:1  
刘庆  张洪信  楚杰  李震 《工业催化》2010,18(7):50-53
合成了绿色杂多酸盐催化剂磷钨酸铝,将苯甲醛(环己酮)和乙二醇的缩合反应作为探针反应,对催化剂的催化活性进行评价。研究了催化剂用量、醛醇物质的量比、反应时间和带水剂用量等因素对收率的影响,结果表明,在醛(酮)为0.2 mol、n[醛(酮)]∶n(醇)=1.0∶1.5、催化剂用量0.6g、带水剂环己烷用量18mL和一定温度下回流反应2.0 h,苯甲醛乙二醇缩醛收率达88.76%,环己酮乙二醇缩酮收率达87.12%。磷钨酸铝具有较好的稳定性,重复使用4次,仍保持较高催化活性。  相似文献   

11.
Functionalized polymer membranes have been used as sensor materials for fabrication of electronic tongue. Here, we report the synthesis and characterization of a novel poly(N‐[4H‐1,2,4‐triazol‐4‐yl]acrylamide) (PNTA) for liquid phase aliphatic alcohol sensing in the form of membranes prepared after blending with poly(vinyl chloride) (PVC). Three PNTA‐PVC based membranes were prepared for sensing of six aliphatic alcohols. Polymer membranes were characterized by spectroscopic techniques. Polar groups on PNTA molecules contribute to the alcohol sensing characteristics. The membrane electric potential, generated by the interaction between membrane surface and aqueous aliphatic alcohols, was monitored with the developed multi‐channel electrode based prototype sensing system (MEBPSS). The polymer membranes showed distinct and repeatable response patterns toward different aliphatic alcohols. Among them PNTA‐PVC12 membrane showed maximum discrimination ability due to the PNTA molecules on the membrane surface with highest charge density as ascertained from field emission scanning electron microscopic studies. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44675.  相似文献   

12.
应用Sol-gel法成功合成了纳米SrTiO3粉体。酞酸丁酯和氯化锶为金属离子源,先驱体以甲醇为溶剂、柠檬酸为螯合剂、乙酰丙酮为稳定剂、聚乙二醇和聚乙烯醇为模板。干先驱体经700℃1h烧成后得到纯的SrTiO3粉体。研究了表面活性剂对粉体的粒子尺寸和形貌的影响。合成粉体的聚乙二醇诱导了均匀的较小的圆形粒子。聚乙烯醇则使合成粉体为较大尺寸的长板柱状的粒子。  相似文献   

13.
邵芬娟  杨群  陆大年 《粘接》2009,30(12):48-51
以1,4-反丁烯二酸和一缩二乙二醇(DEG)为原料,采用缩聚法合成端羟基不饱和聚酯,并采用红外光谱分析(FT—IR)、羟值、酸值、黏度等对所得聚合物进行表征,确认了其分子结构.对其降解性进行研究,并且与1,4-丁二酸与一缩二乙二醇合成的饱和脂肪族聚酯进行了对比。研究结果表明,不饱和脂肪族聚酯和饱和脂肪族聚酯的生物降解性差别不大,也就是双键的引入对其生物降解性没有大的影响;但是不饱和脂肪族聚酯膜经过高温处理后,双键会打开发生交联,而交联后的不饱和脂肪族聚酯的生物降解性变差,而且交联度越高,生物降解性越差。  相似文献   

14.
以1,4环己烷二甲醇、戊二酸和2丙基庚醇为原料,采用酯化缩聚法,以钛酸四正丁酯为催化剂、环己烷为带水剂,合成了新型的聚戊二酸1,4环己烷二甲醇酯增塑剂。目标分子结构中含有六元脂环、线性碳链及酯基的多官能团组成,通过傅里叶变换红外光谱仪、核磁共振谱仪和高效液相色谱仪等对聚酯的结构、相对分子质量进行表征。结果表明,制备的聚酯作为增塑剂混合到聚氯乙烯(PVC)中,PVC/聚酯复合材料的断裂伸长率为677.15 %,而PVC/邻苯二甲酸二辛酯(DOP)复合材料的断裂伸长率在相同测试条件下为693.82 %,聚酯与DOP在加入到PVC中的拉伸性能相差不大,但是,PVC/聚酯复合材料耐热性相对于PVC/DOP复合材料来说提高了158 ℃,并且在活性炭中的迁移性降低了16 %;PVC/聚酯复合材料相对于PVC/DOP具有较好的耐热性和耐迁移性。  相似文献   

15.
采用水相悬浮聚合法合成了PVC-BA共聚物。红外光谱和核磁共振证明:共聚产物PVC-BA具有接枝结构。凝胶渗透色谱(GPC)测试结果发现:PVC接枝聚合后分子量变大,分布变宽。采用透射电镜(TEM)研究反应前后PVC颗粒内部结构形态的变化,证明在PVC初级粒子间孔隙中BA发生了原位接枝反应。热失重分析(TG)表明:PVC-BA共聚物的热稳定性较PVC有改善。  相似文献   

16.
Effects of individual and composed poly(vinyl alcohol) (PVA) suspending agents on the particle morphology of poly(vinyl chloride) (PVC) resins were investigated and discussed in the view of PVA absorption at the oil/water interface and interfacial behavior. It was shown that the percentage and surface coverage of PVA at the oil/water interface decreased with the increase of the degree of hydrolysis (DH) of PVA in the DH range of 70–98 mol %, while the interfacial tension of VC/PVA aqueous solution increased linearly with the increase of DH of PVA. PVC resin with more regular particle shape, increased agglomeration and fusion of primary particles, lower porosity and higher bulk density, was prepared by using PVA with a higher DH as a suspending agent. This was caused by the occurrence of drop coalescence at the very early stage of VC polymerization, the increase of particle shrinkage, and the lower colloidal protection to primary particles. It was also shown that the interfacial tension of VC/water in the presence of composed PVA suspending agents varied linearly with the weight composition of the composed PVA suspending agents. The particle properties of PVC resin prepared by using the composed PVC suspending agents were usually situated in between the properties of PVC resins prepared by using the corresponding individual PVA suspending agent. The particle morphology and properties of PVC resin could be controlled by the suitable choice of the composed PVA suspending agents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3848–3855, 2003  相似文献   

17.
王华  刘晓明 《塑料》2005,34(1):56-60
使用自主合成的端羧基聚酯和端叔胺基羧酸分别对水乳液中的nano-CaCO3进行表面处理,制备了可与PVC形成界面分子物理纠缠或热可逆交联的强界面结合能力的nano-CaCO3.研究了PVC-U/nano-CaCO3的力学性能与CaCO3的表面性质、填充量及表面处理剂分子量等因素的关系.研究结果表明,提高界面结合强度可改善CaCO3在基材中的分散状况并提高PVC-U/nano-CaCO3的屈服强度,却对于提高PVC的冲击能力无明显效果.  相似文献   

18.
A chemical reduction method for preparing monodispersed pure-phase copper colloids in water and ethylene glycol has been reported. Owing to the reduction property of ethylene glycol, the reaction rate in ethylene glycol is higher than that in water. In addition, the amount of reducing agent can be reduced largely. Ascorbic acid plays roles as reducing agent and antioxidant of colloidal copper, due to its ability to scavenge free radicals and reactive oxygen molecules. Thermogravimetric results reveal that the as-prepared copper nanoparticles have good stability, and they begin to be oxidized at above 210 °C. Polyvinyl pyrrolidone works both as size controller and polymeric capping agents, because it hinders the nuclei from aggregation through the polar groups, which strongly absorb the copper particles on the surface with coordination bonds.  相似文献   

19.
黄志辉  包永忠  潘鹏举 《化工学报》2017,68(6):2569-2576
合成了含黄原酸酯端基的聚乙二醇(X-PEG-X)大分子链转移剂,并以其为可逆加成-断裂链转移试剂调控氯乙烯(VC)溶液和悬浮聚合,合成聚氯乙烯-b-聚乙二醇-b-聚氯乙烯(PVC-b-PEG-b-PVC)三嵌段共聚物。X-PEG-X调控VC溶液聚合得到的共聚物的分子量随聚合时间增加而增大,分子量分布指数小于1.65。X-PEG-X具有水/油两相分配和可显著降低水/油界面张力的特性,以X-PEG-X为链转移剂和分散剂,通过自稳定悬浮聚合也可合成PVC-b-PEG-b-PVC共聚物,共聚物颗粒无皮膜结构,分子量随聚合时间增加而增大;由于VC悬浮聚合具有聚合物富相和单体富相两相聚合特性,共聚物分子量分布指数略大于溶液聚合共聚物。通过乙酸乙烯酯(VAc)扩链反应进一步证实了PVC-b-PEG-b-PVC的“活性”,并合成PVAc-b-PVC-b-PEG-b-PVC-b-PVAc共聚物。水接触角测试表明PVC-b-PEG-b-PVC的亲水性优于PVC。  相似文献   

20.
Two series of unsaturated polyesters (UPE from isophthalic acid, fumaric acid, and propylene glycol) were prepared. In series-A resins, UPEs wee thickened with isocyanate-terminated saturated aliphatic polyestes, i.e., an isocyanate-terminated polycaprolactone diol (PE-di-OL), through reaction of the isocyanate group with the hydroxyl group of the UPE. In series-B resins, the UPEs were mixed with saturated aliphatic polyesters i.e., PE-di-OL. The curing reaction of these two series of UPEs with styrene was studied by using differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). The DSC data show that for a fixed PE-di-OL molecular weight, the curing reaction rate of series-A UPE is faster than that of series-B UPE. The variation of microgel size during curing ws studied by GPC. These results revealed that microgel formation has a great effect on the kinetics of cure for the unsaturated polyester-styrene system. The curing of these two series of UPEs is found to strongly depend on the compatibility of the components in the curing system.  相似文献   

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