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《精细化工》2013,(5)
从聚丁二酸丁二醇酯(PBS)的环状低聚物中分离提纯出了PBS的环状二聚物〔cyclic dimer of poly(butylenesuccinate),CDBS〕,采用核磁、质谱对该环状二聚物进行了表征,研究表明,通过分离纯化得到了纯度高的PBS的环状二聚物。以纯化的CDBS为原料、十二醇为初始剂、辛酸锡作催化剂,采用开环聚合的方法合成了PBS,采用核磁、红外光谱对合成的PBS的结构进行了表征,并研究了开环聚合温度、聚合时间以及催化剂用量对PBS的分子量、单体转化率的影响,结果表明,开环反应温度220℃左右,反应3 h,PBS的相对分子质量(简称分子量,下同)可达到63 300,与直接酯化-缩聚法相比,采用开环聚合法能提高PBS的制备效率。 相似文献
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以丁二酸(SA),1,4-丁二醇(BDO)为原料,通过熔融聚合法合成聚丁二酸丁二醇酯(PBS)。通过对催化剂筛选及用量、缩聚反应温度、总反应时间和酸醇比等因素对产品粘均分子量影响的探讨,优化出了熔融法合成PBS的最佳工艺条件:选择SnCl2做催化剂,用量在2%(以催化剂加入SA的质量比表示),缩聚反应温度在230℃,总反应时间5h,在酸醇配比为1∶1.1时,反应得到的PBS产品的粘均分子量最大,粘均分子量为5.14×104g/mol,产品颜色为白色。用IR、TG、1H-NMR等表征证明产品合成成功。 相似文献
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研究了含氯前聚物法合成聚萘乙炔中催化剂、单体浓度、碱滴加速度、反应介质、反应温度对前聚合物产率、分子量等的影响。用红外光谱(FTIR)、核磁(NMR)、色谱-质谱(GC-MS)、元素分析等手段对聚合物进行了表征。 相似文献
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脂肪酶催化液-固反应合成聚丁二酸丁二酯 总被引:3,自引:1,他引:2
以固定化酶Novozyme435为催化剂,在液-固混合体系中经酶催化1,4-丁二醇与丁二酸缩聚合成聚丁二酸丁二酯(PBS),考察反应条件对聚合效果的影响。采用GPC法对产物重均分子量Mw和分子量分布MwMn进行了测定;采用核磁共振法对产物结构进行了鉴定。最佳反应条件为:丁二酸与1,4-丁二醇的物质的量的比为17:23,Novozyme435用量为底物总质量的7%,聚合温度为65℃。以底物总质量200%的二苯醚为反应介质,真空条件下聚合48h,PBS的最大Mw可达到50800(MwMn=1.36)。实验表明,丁二酸在反应介质中的溶解程度和副产物水的去除是限制PBS聚合效果的最主要因素。 相似文献
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利用三亚甲基碳酸酯在1,4-丁二醇链转移剂和辛酸亚锡催化剂的作用下开环聚合,合成三种不同低分子量的聚(三亚甲基碳酸酯)二元醇。通过傅里叶变换红外光谱仪、核磁共振仪、凝胶渗透色谱仪、热重分析仪和差示扫描量热仪对产物进行表征。红外分析和核磁表征表明聚合物结构与预设的分子结构相吻合;凝胶渗透色谱法表明聚合物的分子量具有多分散性,多分散系数在1.5左右。热性能分析表明聚合物的玻璃化转变温度低于室温,拓宽了聚(三亚甲基碳酸酯)二元醇在较低温反应中的应用。热分解温度在200℃左右,能满足聚合物合成及加工工艺的热性能要求。 相似文献
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该研究采用溶液熔融聚合法对聚丁二酸丁二醇酯(PBS)进行合成,采用控制变量法进行反复实验,以反应后的出水量及合成产物的颜色为实验指标分别讨论了合成聚丁二酸丁二醇酯的影响因素:即反应温度、时间及催化剂对合成条件的影响,分析得出了最优的合成工艺条件。 相似文献
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A macrocyclic lactone (BSD) consisting of butylene succinate dimer was successfully isolated from oligomeric byproducts of poly(butylene succinate) (PBS) prepared by the polycondensation method. BSD was subjected to ring-opening polymerization (ROP) with tin octoate as the catalyst to obtain PBS. Its number-average molecular weight was found to reach about 9.5 × 104 Da, being much higher than that of the PBS sample obtained by direct melt polycondensation. When the ROP of BSD was performed in the presence of polyethylene glycol (PEG) as the macro-initiators, triblock (PBS-PEG-PBS) and diblock (PEG-PBS) copolymers were obtained. 相似文献
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Jian-Bing Zeng 《Polymer》2009,50(5):1178-2282
A novel biodegradable multiblock poly(ester urethane) (PEU), consisting of poly(l-lactic acid) (PLLA) and poly(butylene succinate) (PBS) blocks, has been successfully synthesized via chain-extension reaction of dihydroxyl terminated PLLA (PLLA-OH) and PBS prepolymers (PBS-OH) using toluene-2,4-diisocyanate (TDI) as a chain extender. The chemical structures and molecular weights of PEUs, containing different block lengths and weight fractions of PLLA and PBS, were characterized by 1H NMR and GPC. The effects of the structures on the physical properties of PEUs were systematically studied by means of DSC, TGA, WAXD and tensile testing. The DSC results indicated that PLLA segment was compatible well with PBS segment in amorphous phase and the crystallization of PEU was predominantly caused by PBS segment, which was also confirmed by WAXD. The results of tensile testing showed that the extensibility of PLLA was largely improved by incorporating PBS segment. The PEU can be used as a potential substitute for some petroleum-based thermoplastics. 相似文献
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Chao Qun Huang Si Yang Luo Shao Yi Xu Jing Bo Zhao Sheng Ling Jiang Wan Tai Yang 《应用聚合物科学杂志》2010,115(3):1555-1565
Low‐molecular‐weight HOOC‐terminated poly(butylene adipate) prepolymer (PrePBA) and poly(butylene succinate) prepolymer (PrePBS) were synthesized through melt‐condensation polymerization from adipic acid or succinic acid with butanediol. The catalyzed chain extension of these prepolymers was carried out at 180–220°C with 2,2′‐(1,4‐phenylene)‐bis(2‐oxazoline) as a chain extender and p‐toluenesulfonic acid (p‐TSA) as a catalyst. Higher molecular weight polyesters were obtained from the catalyzed chain extension than from the noncatalyzed one. However, an improperly high amount of p‐TSA and a high temperature caused branching or a crosslinking reaction. Under optimal conditions, chain‐extended poly(butylene adipate) (PBA) with a number‐average molecular weight up to 29,600 and poly(butylene succinate) (PBS) with an intrinsic viscosity of 0.82 dL/g were synthesized. The chain‐extended polyesters were characterized by IR spectroscopy, 1H‐NMR spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis, wide‐angle X‐ray scattering, and tensile testing. DSC, wide‐angle X‐ray scattering, and thermogravimetric analysis characterization showed that the chain‐extended PBA and PBS had lower melting temperatures and crystallinities and slower crystallization rates and were less thermally stable than PrePBA and PrePBS. This deterioration of their properties was not harmful enough to impair their thermal processing properties and should not prevent them from being used as biodegradable thermoplastics. The tensile strength of the chain‐extended PBS was about 31.05 MPa. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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为了探讨线性PBS基脂肪族共聚酯的结构和降解之间的关系,首先合成了线性PBS基脂肪族共聚酯,即聚丁二酸丁二醇酯-共-聚己二酸丁二醇酯P(BS-co-BA),聚丁二酸丁二醇酯-共-癸二酸丁二醇酯P(BS-co-BSe),并将线性PBS基脂肪族共聚酯及PBS在土壤悬浮液中进行降解,通过GPC、熔点测定仪对线性PBS基脂肪族共聚酯的分子量和熔点进行了测定;通过测定降解过程中失重率和降解前后聚酯薄膜表面形貌来对共聚酯降解程度进行表征。结果表明:随着二元酸碳链的增长,分子对称性降低,降解性能增大。通过观察分子量,熔点及降解失重率的测定结果,得出分子量越大,降解越不容易进行;熔点越小,降解性能越好。 相似文献
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Xi Huang Chuncheng Li Liuchun Zheng Dong Zhang Guohu Guan Yaonan Xiao 《Polymer International》2009,58(8):893-899
BACKGROUND: To obtain a biodegradable thermoplastic elastomer, a series of poly(ester‐ether)s based on poly(butylene succinate) (PBS) and poly(propylene glycol) (PPG), with various mass fractions and molecular weights of PPG, were synthesized through melt polycondensation. RESULTS: The copolyesters were characterized using 1H NMR, gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, mechanical testing and enzymatic degradation. The results indicated that poly(ester‐ether)s with high molecular weights were successfully synthesized. The composition of the copolyesters agreed very well with the feed ratio. With increasing content of the soft PPG segment, the glass transition temperature decreased gradually while the melting temperature, the crystallization temperature and the relative degree of crystallinity decreased. Mechanical testing demonstrated that the toughness of PBS was improved significantly. The elongation at break of the copolyesters was 2–5 times that of the original PBS. Most of the poly(ester‐ether) specimens were so flexible that they were not broken in Izod impact experiments. At the same time, the enzymatic degradation rate of PBS was enhanced. Also, the difference in molecular weight of PPG led to properties being changed to some extent among the copolyesters. CONCLUSION: The synthesized poly(ester‐ether)s having excellent flexibility and biodegradability extend the application of PBS into the areas where biodegradable thermoplastic elastomers are needed. Copyright © 2009 Society of Chemical Industry 相似文献
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以丁二酸、1,4–丁二醇为原料,采用溶液–熔融法合成了不同相对分子质量的聚丁二酸丁二酯(PBS),并研究了4种不同催化剂合成PBS反应的催化性能。采用凝胶渗透色谱(GPC)、傅里叶变换红外光谱(FTIR)、核磁共振氢谱(1H–NMR)、差示扫描量热(DSC)、热重(TG)分析和力学拉伸仪对产物的结构、热稳定性、相对分子质量、力学性能等进行表征。结果表明,不同催化剂催化合成的PBS相对分子质量大小顺序为:对甲苯磺酸钛酸异丙酯氯化亚锡醋酸锌无催化剂。相对数均分子质量最大值为5.57×10~4,最小值为2.54×10~4。所有合成的PBS的热分解温度均大于250℃,都具有较好的热稳定性。其中以钛酸异丙酯和氯化亚锡为催化剂时,得到的PBS具有良好的力学性能。综上结果,钛酸异丙酯为催化剂时合成的PBS最优,相对分子质量为5.50×10~4,拉伸强度为34.5 MPa,断裂伸长率高达201%。 相似文献
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1,2-丙二醇对可生物降解聚丁二酸丁二醇酯的共聚改性 总被引:2,自引:0,他引:2
以丁二酸、丁二醇和1,2-丙二醇为原料,采用溶液结合熔融缩聚合成法,得到了一系列聚(丁二酸丁二醇酯-co-丁二酸1,2-丙二醇酯)共聚物P(BS-co-PS)。利用1HNMR、GPC和X射线衍射等方法对共聚物的组成、分子量及其分子量分布、热学性能、结晶性能、力学性能等进行了研究。结果表明:反应4h,即可得到数均分子量60000以上的聚(丁二酸丁二醇酯-co-丁二酸1,2-丙二醇酯)共聚物P(BS-co-PS),分子量分布均小于2.0;随着1,2-丙二醇添加量的增加,共聚物的结晶度降低,熔点下降,但断裂伸长率明显增加,当添加量为30%(摩尔分数)时,断裂伸长率达到417%,表明共聚物具有良好的延展性能;所有共聚物的热分解温度均在300℃以上,具有良好的热稳定性。 相似文献