不饱和脂肪族聚酯生物降解性的研究

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。     

生物降解性脂肪族聚酯改性的研究进展

综述了脂肪族聚酯改性制备生物降解性聚酯的研究进展.在聚酯中引入刚性链段(即将脂肪族聚酯与芳香族、液晶基元共聚合)可改善聚酯的加工性能;在聚酯中引入亲水基大分子(即将脂肪族聚酯淀粉共混或与聚乙二醇共聚合)可改善聚酯的亲水性能.今后脂肪族聚酯改性研究的重点将解决功能化基团的引入、合成路线的简化、成本的降低及改性的效果等方面的问题.     

Synthesis and enzymatic degradation of high molecular weight aliphatic polyesters

The aliphatic polyesters with high molecular weight have been prepared according to two methods. First is the synthesis of the polyesters by polycondensation of dimethyl succinate (DMS) with 1,4‐butanediol (BD) using various metal alkoxides as a catalyst. Among the metal alkoxides used, titanium tetraisopropoxide [Ti(OiPr)₄] gave the best results (highest molecular weight and yield). Thus, we have prepared aliphatic polyesters using a variety combinations of diesters [MeOOC—(CH₂)_x—COOMe, x = 2–8] with BD by the catalysis of Ti(OiPr)₄. The polyesters with high number‐average molecular weight (M_n > 35,000), except dimethyl adipate (DMA, x = 4)/BD polyester (M_n = 26,900), were obtained in high yield. The melting temperatures (T_m) of polyesters were relatively low (43.4–66.8°C) except that (115.6°C) of the DMS/BD polyester. Second is the synthesis of high molecular weight polyesters by chain extension reaction of lower molecular weight (M_n = 15,900–26,000) polyesters using hexamethylene diisocyanate (HDI) as a chain extender. The M_n values of chain‐extended polyesters consequently increased more than two times (M_n = 34,700–56,000). The thermal properties of polyesters hardly changed before and after chain extension. Enzymatic degradations of the polyesters were performed using three different enzymes (cholesterol esterase, lipase B, and Rhizopus delemar lipase) before chain extension. The enzymatic degradability varied depending on both thermal properties of polyesters [melting temperature and heat of fusion (crystallinity)] and the substrate specificity of enzymes, but it was the following order: cholesterol esterase > lipase B > R. delemar lipase. The ¹H‐NMR spectrum of water‐soluble degraded products of the polyester indicated that the polyester was degraded into a condensation product of diol with diester in a monomer form. The enzymatic degradation of chain extended polyesters was slightly smaller than that before chain extension, but proceeded steadily. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 340–347, 2001     

Network polyester films from glycerol and dicarboxylic acids

This paper presents information on the preparation of the network polyester films from glycerol (Y_g) and aromatic dicarboxylic acids of phthalic anhydride (P), dimethyl isophthalate (I) and dimethyl terephthalate (T), as well as aliphatic dicarboxylic acids of adipic, sebacic, 1, 10-decanedicarboxylic and 1, 12-dodecanedicarboxylic acids, and their properties. Y_g and dicarboxylic acid were polycondensed immediately before the gelation started. The prepolymers obtained were cast from DMF solution and successively post-polymerized at various temperatures and times to form networks. The resultant films were transparent, flexible and insoluble in organic solvents. Heat distortion temperature (T_h) measured by a penetration mode of thermomechanical analysis increased with increasing post-polymerization temperature and time, and then leveled out. T_h values corresponded well to the glass transition temperature (T_g) measured by differential thermal analysis (DTA). T_h was 152°C, 162°C and 197°C for Y_gP, Y_gI and Y_g T post-polymerized at 270°C for 6 h, respectively. T_h values of network films made from aliphatic dicarboxylic acids could not be observed until complete probe penetration occurs, as a result of thermal decomposition because the T_g is lower than room temperature. The degree of reaction estimated from the IR absorbance of hydroxyl and methylene groups was in the range of 60–80%. Two diffraction peaks appeared in the wide-angle X-ray scattering pattern, suggesting some ordered structure owing to the regular networks. Density decreased with increasing post-polymerization time and temperature, in the order Y_gP > Y_gI > Y_gT. Network films made from aliphatic dicarboxylic acids had much lower tensile strength and Young's modulus, and greater elongation, than those made from dicarboxylic acids, as a result of the T_g being below room temperature.     

聚酯生物降解及评价方法研究

塑料“白色污染”越来越引起人们的广泛关注,在自然界微生物的作用下能降解成为二氧化碳、水和无机物的生物降解材料是解决问题的一种有效途径。新型生物降解聚酯的开发离不开对材料生物降解性能的研究和评价方法的开发,为此,本文评述了生物降解聚酯的类型及其生物降解性能、聚酯降解微生物与酶的研究进展,介绍了土壤、堆肥和水体环境中的材料生物降解性评价方法。可以看到低成本、高性能是生物降解聚酯的发展方向;现有聚酯降解微生物和酶尚不能满足聚酯工业回收应用要求,需开发更高效、更稳定的酶;目前生物降解评价方法受接种环境影响大、评价周期长且难完全模拟材料在自然环境中生物降解行为,新型生物降解聚酯的开发也亟需可靠、快速的降解评价方法。     

Synthesis and enzymatic degradation of regular network aliphatic polyesters

Regular network aliphatic polyesters were prepared from glycerol (Yg) and a series of various length aliphatic dicarboxylic acids (HOOC-(CH2)_n−2-COOOH, n = 4–10, 12 and 14). Prepolymers prepared by melt polycondensation were cast from dimethylformamide solution and post-polymerized at 230°C for various times to form a network. The resultant films were transparent, flexible and insoluble in organic solvents. The degree of reaction (D_R) estimated from the infrared absorbance of -OH and >CH₂ or >CH groups increased with increasing post-polymerization time and length of methylene chain. The heat distortion temperature also increased with increasing post-polymerization time and was 55, 28, 15, 6, 0, −1, −5, 4 and 32°C for Yg4, Yg5, Yg6, Yg7, Yg8, Yg9, Yg10, Yg12 and Yg14 post-polymerized for 4 h, respectively. Wide angle X-ray scattering patterns showed a distinct single diffraction peak, suggesting some ordered structure due to the establishment of a regular network. Density, water absorption and weight loss by alkali hydrolysis decreased with increasing methylene chain length. The enzymatic degradation was estimated by weight loss of the network films in a buffer solution of lipase at 37°C. The films of Yg4, Yg5, Yg6 and Yg7 showed no weight loss, but the weight loss increased greatly for Yg8, Yg9 and Yg10, and then decreased abruptly for Yg12 and Yg14. This suggests that the enzymatic degradation is affected by network structure, which allows the lipase to penetrate, and by the concentration of the enzymatically degradable ester linkage.     

A new method of synthesis of alkyl-glycidyl esters of dicarboxylic acids in high yields

A series of new alkyl-glycidyl esters of dicarboxylic acids which could be used as PVC plasticizers were synthesized. The method adopted is a new synthetic process which can be carried out in two stages. During the first stage, the carboxylic acid anhydride reacts with the salt of the alcohol, and the sodium salt produced reacts with epichlorhydrin in the presence of a catalyst to yield an alkyl-glycidyl ester. The specific reactions give pure products in high yields. The reaction of phthalic acid bisodium salt with epichlorhydrin, as well as the reaction of phthaloyl chloride with glycidol, gave diglycidyl phthalate in 36% and 22% yields, respectively.     

脂肪族聚酯基可生物降解水性聚氨酯的合成

以自合成的脂肪族聚酯二元醇为原料,合成了可生物降解水性聚氨酯乳液。研究了二元醇结构中不同的乳酸/己二酸比例对聚氨酯乳液的粒径、亲水性及生物降解性的影响。结果表明:随着乳酸含量的增加,乳液的平均粒径出现一极小值;当乳酸含量为25%时,由聚氨酯乳液得到的胶膜的亲水性最好;随着乳酸含量的增加,水性聚氨酯的可生物降解性能呈增大趋势。     

Synthesis,characterization and biodegradation studies of chain‐coupled polyesters based on tartaric acid

A series of chain‐coupled polyesters based on tartaric acid was synthesized and characterized following a two‐step procedure. In the first step, tartaric acid based hydroxyl terminated polyesters with various alkane diols were prepared and then, in a second step, a chain‐coupling approach using hexamethylene diisocyanate was employed on the synthesized polyesters to prepare a series of chain‐coupled polyesters. The number‐average molecular weights (M_n) of the polyesters were found to vary in the range (4.8 ? 28.1) × 10³ g mol^?1. Thermomechanical studies demonstrate that the storage modulus of the chain‐coupled polyesters decreases with increasing polymethylene chain length which is attributable to enhanced flexibility. The isolation of bacteria on medium containing polymer as the sole source of carbon indicates the ability of the synthesized polyesters to be taken up by microorganisms for growth. © 2013 Society of Chemical Industry     

Synthesis and characterization of crosslinked polyurethane dispersions based on hydroxylated polyesters

Stringent environmental regulation has endowed dispersible coatings with excellent property profiles in industrial applications. In this aspect, aqueous polyurethane dispersions (PUDs) are of special interest. The present study reports on the synthesis of hydroxylated polyester (HP) based polyurethane polyols containing internal carboxyl group with different diisocyanates. These polyurethane polyols were partly acetoacetylated with ethyl acetoacetate to incorporate β‐ketoester in the polyurethane polyol backbone. The synthesized polyols were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and differential scanning calorimetry. Polyurethane polyols and their acetoacetylated cousins were used to develop PUDs. Particle size of the reactive PUDs was evaluated by a particle size analyzer. PUDs were crosslinked with hexamethoxy methyl melamine and their film properties were studied by dynamic mechanical and thermal analyzers and thermogravimetric analyses. The effects of different diisocyanate and acetoacetylation on the stability of reactive dispersion and properties of the crosslinked films were evaluated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 368–380, 2006     

混合二元酸制备多元膦酸缓蚀阻垢剂研究

混合二元酸是环己烷氧化制己二酸生产过程中的副产品，其中含有丁二酸、戊二酸、己二酸等组分，其组成复杂，尽管价格便宜，但分离成本高，不经过分离进行综合利用受到很大的限制。实验不但成功地分别以戊二酸、己二酸为原料合成出新型的同碳二膦酸，而且根据多组分缓蚀阻垢剂的协同效应原理，采用组成复杂的混合二元酸一步合成出混合多元膦酸。对纯二元酸合成的产品和混合二元酸合成的产品缓蚀组垢性能进行了比较。实验结果表明，混合二元酸合成的产品作为水处理剂具有优良的缓蚀和阻垢作用。     

金属离子对脂肪族聚酯降解性能的影响

在土壤培养液中添加不同种类的金属离子,研究了它们对可生物降解聚酯聚乳酸（PLA）、聚丁二酸丁二酯（PBS）膜降解性能的影响。采用傅里叶变换红外光谱仪表征了PLA和PBS膜降解前后的化学结构。结果表明：所有降解后的膜表面均有明显被侵蚀的痕迹;在土壤培养液中的Mg^2＋,Zn^2＋,Ca^2＋对PLA的降解性能有促进作用,对PBS的降解性能则影响不大;降解后PLA膜的玻璃化转变温度有所升高,但PBS膜变化不大。     

钛硅复合氧化物催化合成长链二元腈

以四氯化钛和硅酸乙酯为原料,制备了复合氧化物催化剂TiO2-SiO2(TSO),应用于催化十三碳二元酸氨化反应制得十三碳二元腈。按正交实验设计方法考察了催化剂组成、催化剂用量、温度、反应时间、搅拌速度及氨气流量对反应的影响。结果表明,最佳反应条件为:钛硅原子个数比3∶1,采用程序升温方式(280℃2 h,300℃3 h,320℃1 h),催化剂用量为酸质量的10%,搅拌速度1000 r/min,氨气流量120 L/h。最佳反应条件下制备的产物十三碳二腈的质量分数达96.70%,收率达86.28%。用TLC、IR、GC-MS检测产物的纯度和结构,并合成了一系列长链二元腈。     

Polyarylates (polyesters from aromatic dicarboxylic acids and bisphenols)

After a short review on the literature of aromatic polyarylates synthesis the following aspects are described: preparation of some monomers; preparation of the polymers by different chemical processing routes; physical properties; moulding behaviour. Amorphous polymers are especially considered. Figures on continuous melt condensation via the diphenylester route are given. Some polyarylates have attractive mechanical and electrical properties. Injection moulding is only possible if the glass temperature is not too high (≤200°C), and even with these polymers thermal decomposition during injection moulding is a limiting factor for their technical use. The weak point is the ester group. Extrusion, pressing, and solution casting are technically feasable.     

Synthesis of polyesters as binders for deinkable inks. II. Kinetics and mechanism of polyesterification between o-phthalic anhydride and neopentyl glycol in bulk at 200°C

The kinetics of the polyesterification in bulk at 200°C between o-phthalic anhydride and neopentyl glycol (2,2-dimethyl-1,3-propanediol) in a nonequimolecular ratio and in the absence of an external catalyst was investigated. The formation of the monoester and two dimeric compounds by uncatalyzed heating of o-phthalic anhydride with neopentyl glycol was virtually complete after dissolution of the anhydride. The data were analyzed statistically by a mathematical method due to Fradet and Maréchal for the estimation of the orders of reaction. This statistical adjustment of the data analysis supports the assumption that the kinetics of polyesterification in the absence of both the solvent and catalyst may be fitted to several orders of reaction over all the conversion. At first, our experimental data may be fitted to 3, or , or 2, etc., overall orders. The results establish that the overall kinetic order of the polyesterification depend upon the goodness of the experimental results and cannot be only selected by means of a correlation coefficient. If this last criterium is adopted, the polyesterification at low, medium, as well as at high conversions may be 3 as the most probable one, order one with respect to acid group concentration, and order two with respect to alcoholic group concentration, in agreement with Flory's predictions. A mechanism consistent with the most plausible kinetic results (I_m,n = 0.9990 and m, n = 1, 2) is proposed. It consists of a dimerization of the alcoholic groups followed by an attack of the acid to the dimer. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2409–2431, 1997     

C-21 dicarboxylic acids in soap and detergent applications

A unique polycarboxylic acid, 5(6)-carboxy-4-hexyl-2-cyclohexene-1-octanoic acid, has been available commercially for over 15 years. A new high-purity (>97%), light-color version of the C-21 dicarboxylic acid has been developed recently. Soaps of the C-21 dicarboxylic acid can be used as hydrotropes to increase the solubility of nonionic surfactants in aqueous solutions containing builders and/or anionic surfactants. Since these soaps are anionic fatty acid derivatives, they reduce the surface tensions of formulations, thus improving detergency. The nontoxic and biodegradable nature of this dicarboxylic acid makes it an attractive formulation component. This paper outlines application evaluations of the soaps prepared from the C-21 dicarboxylic acids. These evaluations demonstrate how the soaps interact with nonionic surfactants or pine oil to provide clear formulations, how they wet cotton skeins in neutral to highly alkaline solutions, and how they inhibit gel formation when preparing high-solids fatty acid soap solutions. Furthermore, the preparation and characterization of the soaps of the C-21 dicarboxylic acid products are discussed. Mass-balance equations describe the preparation of aqueous soap solutions at any given concentration. Characterization of the resulting soap solutions includes acid number, pH, color, color stability, foam stability, surface tension as a function of concentration, and hard-water compatibility.     

Synthesis and characterization of new aliphatic polyesters containing methanodinaphtho[1,3]dioxocin part

A novel dinaphthodioxocin‐containing diol monomer, 8,16‐methano‐16H‐dinaphtho[2,1‐d:1′,2′‐g][1,3] dioxocin‐2,14‐diol (MDDD) was synthesized in high yield and purity through the condensation of 2,7‐dihydroxynaphthalene with malonaldehydetetramethyl acetal at room temperature. It is used as a new monomer for the synthesis of a series of novel dinaphthodioxocin‐containing aliphatic polyesters by interfacial polycondensation method. The new diol monomer was fully characterized by IR, NMR, mass spectroscopies, and elemental analysis. Optimal conditions for polyesterification were obtained via study of the model compounds. Polyesters derived from MDDD and four aliphatic diacid chlorides had inherent viscosities ranging from 0.26 to 0.38 dL/g. The chemical structure of the polymers was fully characterized by IR, NMR spectroscopies, and elemental analysis. The physical properties of the polymers were studied. All the new polymers show good thermal stability and very good solubility in most organic solvents. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

蔗糖脂肪酸多酯的合成方法及性能研究进展

概述了在不同溶剂及催化剂体系中蔗糖脂肪酸多酯的研究工作,介绍了蔗糖脂肪酸多酯的合成工艺,包括溶剂法、无溶剂法和相转移催化法等不同的制备方法;重点综述了无溶剂酯交换二步法合成蔗糖脂肪酸多酯的工艺;并展望了其生物合成法的可行性。从乳化性能、生理活性、毒性、氧化稳定性和热稳定性以及生物降解性等方面简要介绍了蔗糖脂肪酸多酯的性能。     

Effect of orientation on the biodegradability of uniaxially stretched aliphatic copolyester films

The effects of uniaxial drawing conditions on the orientation of aliphatic copolyester films were investigated by using both Fourier transform infrared-attenuated total reflection (FTIR-ATR) dichroism and wide angle X-ray diffraction (WAXD) methods. The results showed that orientation in uniaxially drawn films was determined by the drawing rate and drawing temperature. At higher drawing rates and higher drawing temperatures, higher orientation was obtained due to a large deformation of spherulites. The WAXD patterns of drawn films exhibited the preferential orientation of lamellar crystallites. The results of microbial degradation indicated that development of crystalline orientation evidently depressed biodegradability of samples. Video microscopy observations revealed that the degree of orientation played a dominant role in determining the rate of surface erosion. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1999–2006, 1997     

Synthesis and Kinetic Studies on Dimer Fatty Acid/Polyethylene Glycol Polyester

Dimer fatty acid polyethylene glycol polyester, a new kind of non-ionic polymeric surfactant, was synthesized by using dimer fatty acid and polyethylene glycol (400) as materials in this paper. The optimum reaction conditions of esterification were as follows: the molar ratio of dimer fatty acid (DFA)/PEG (400) is 1 / 1.20, the preferable catalyst is stannous chloride and the amount is 0.3% (w/w) of the mass of DFA, reaction temperature is 200°C, reaction time is 6 h. The conversion ratio of polyesterification can reach 98.11%. A new kinetic model of polyesterification reaction catalyzed with stannous chloride was presented. The Genetic Algorithms and Runge–Kutta were used to estimate the parameters of the kinetic model. The results of experiments and computer operations indicated that the reaction order is 0.998 to the carboxyl and 1 order to the hydroxyl. The activation energy obtained from Arrhenius plot is 97.18 kJ mol⁻¹, and the pre-exponential frequency factor is lnA = 21.39 kg² mol⁻² min⁻¹ at temperature range of 160 ∼ 190°C.