生物基聚酯单体2,5-呋喃二甲酸的制备及应用研究进展

化石资源的巨量使用所带来的环境污染、气候变暖和资源能源危机等问题已日益成为全球学术界和产业界关注的焦点,发展绿色可再生生物质资源是当今研究的重中之重.2,5-呋喃二甲酸(FDCA)作为最有价值的生物基平台化合物之一,逐渐受到广泛关注.综述了化学法和生物法制备FDCA的研究进展,介绍了FDCA在聚酯、聚酰胺、金属有机骨架材料、药化合成、增塑剂等方面的应用,并对应用前景和研究趋势进行了展望.     

基于可再生资源含呋喃环聚酯

2,5-呋喃二甲酸（2,5-FDCA）是基于可再生资源的二酸,来源广泛,可由果糖和半乳糖制得。近年来以2,5-呋喃二甲酸为起始原料合成聚合物的研究引起了人们的广泛关注。本文对基于可再生资源含呋喃环均聚酯及共聚酯的合成、结构和性能等方面的研究作了综述,着重阐述了以2,5-呋喃二甲酸及其衍生物为起始原料制备聚酯的新进展,并讨论了基于可再生资源含呋喃聚酯的应用及发展前景。     

对苯二甲酰类全芳族聚酯结构与性能的研究

本文以对苯二甲酰氯分别和五种二元酚单体,对苯二酚(HQ)、邻氯对苯二酚(CHQ)、联苯二酚(BP)、双酚A(BPA)、4,4′-二羟基二苯基甲烷(BPM)进行溶液缩聚,制备了一系列全芳族均聚酯和共聚酯,作了各种性能表征。考虑了单苯二酚和双苯二酚单体对聚合物的熔融温度、热分解温度、相变热效应、溶解性、液晶态及织态结构、液晶相范围和光学行为等影响,并讨论了二酚单体作为致介单元的分子结构条件,得到HQ、CHQ和BP为致介单体,BPA和BPA为非致介单体的结论。     

FDCA基聚酯的合成、性能及应用研究进展

生物质资源是一种储量丰富的可再生资源。生物质资源的高效利用不仅具有非常巨大的经济和生态价值,而且对新能源与生物基合成材料的可持续发展战略具有重大意义。由植物纤维素等生物质材料经生物或者简单化学过程处理,可获得丰富的生物基单体2,5-呋喃二甲酸(FDCA)。FDCA可用于生物基聚酯材料的合成。FDCA系列聚酯材料性能优异,可作为由石油基单体对苯二甲酸(PTA)而合成的芳香族聚酯材料(例如PET)的一种潜在的高性能生物可降解替代材料。本文简要说明了生物基单体FDCA的物性及制备方法,并重点阐述了包括聚呋喃二甲酸乙二酯(PEF)与聚呋喃二甲酸丁二酯(PBF)等一系列FDCA基聚酯材料的合成及性质,同时对FDCA基聚酯材料的应用进展进行了简要介绍,最后对FDCA基聚酯生物基合成材料的发展前景作了初步展望。     

水溶性聚酯的结构和性能

由对苯二甲酸二甲酯、间苯二甲酸、间苯二甲酸二甲酯５－磺酸钠与乙二醇等共缩聚合成的ＰＥＴ型水溶性聚酯（ＷＳＰ）是一种新型的水溶性聚合物，在化纤、纺织、涂料、粘合剂、电子、油墨等领域有着广泛的应用前景．化纤领域超细纤维新材料的研究、开发和生产，迫切需要一...     

共聚酯PEIT-PEG结构与性能的研究

PET与PEG共聚可改善PET的抗静电性，但PEG含量的增加，会使共聚物的结晶温度大幅度地降低，不利于纤维加工，且伴随着结晶的发生，纤维的抗静电性也受到影响。在共聚体系中添加间苯二甲酸(IPA)，不仅能破坏大分子链结构的规整性、降低共聚酯的结晶性，而且能提高共聚酯纤雏的抗静电性能。用DSC与TG对共聚酯(PEIT-PEG)的聚集态结构、热性能、结晶性能等进行了表征。     

Fura-型新荧光试剂的合成和结构与性能关系的研究

本文报道了测定细胞内游离[Ca^2^+]的新荧光试剂Fura-4, Fura-5的合成方法。研究了不同取代基对缩合反应的影响及取代基的结构对荧光性能的影响。     

一类含萘环结构的聚酯酰亚胺液晶聚合物的结构与性能研究

利用Higashi芳香聚酯直接缩聚法的原理,采用分步投料的方法,以N,N′-1,6-亚己基-双苯偏三酸酰亚胺二酸(IA6)、6-羟基-乙-萘甲酸(HNA)和4,4′-二羟基二苯酮(DHBP)为单体原料,合成了一系列聚酯酰亚胺共聚物.用核磁共振(NMR)、差热分析(DSC)、偏光显微镜(PLM)、广角X射线衍射(WAXD)、热重分析(TGA)等手段对所合成的聚酯酰亚胺的液晶行为、结构以及热性能进行了表征.研究结果表明,当HNA投料量占单体总投料量高于33mol%时,所得聚合物均呈明显的向列型热致液晶特性.但是,此类液晶聚合物仅在升温过程中出现液晶的相转变,而在降温过程中并未观察到液晶的相转变行为.由DSC结果分析可知,此类聚合物具有较高的玻璃化转变温度(Tg)和较低的熔融温度(Tm),有望成为一类既具有较低加工温度又有较高使用温度的液晶聚合物材料.     

Gemini型磺基琥珀酸酯钠表面活性剂的结构与性能的关系

以不同的醇为原料,合成了不同的Gemini型磺基琥珀酸酯钠阴离子表面活性剂,对它们的表面化学性能和应用性能进行了测定,并将其性质与其结构的关系进行关联。结果表明:其活性高于相应单基表面活性剂,且联结基、憎水链长度对其活性有影响。联结基长度增加,产物的临界胶束浓度(CMC)降低,对应的表面张力增加,其乳化性、起泡性、稳泡性、渗透力降低,增溶性提高;憎水链长度增加,CMC降低,对应的表面张力先减后增,其乳化性、稳泡性、增溶性提高,起泡性先增后减,渗透力减弱。     

新型呋喃基Schiff碱衍生物的合成、结构和生物活性

席夫碱类化合物具有独特的抗癌、抗菌、抗病毒等生物活性.以多羟烷基呋喃化合物为原料经氧化、脱水得到α,β-不饱和醛,活泼的醛羰基进一步与苯胺类化合物缩合得到8个新的呋喃基Schiff碱化合物,并对合成的化合物进行了初步的生物活性测试.     

试论高聚物结构与性能关系的三个层次

高分子物理的基本任务之一就是探求高聚物的结构与性能,揭示结构与性能之间的内在联系及其基本规律。高聚物结构与性能的关系应该包含3个层次:通过分子运动联系的分子结构与材料性能关系、通过产品设计联系的凝聚态结构与制品性能关系和通过凝聚态物理知识联系的电子态结构与材料功能关系。传统教材上仅讲授结构与性能关系,有相当的局限性,需要在研究生阶段补充有关凝聚态结构与制品性能关系和电子态结构与材料功能关系的课程。     

软段结构对聚氨酯性能影响的研究

用熔融缩聚法俣成了己二酸系和己二酸／芳香二酸混合系两个系列的聚酯；同溶液一步法将部分聚酯与ＭＤＩ反应，形成一系列聚酯型氨酯，以化学分析，ＶＰＯ，ＩＲ，ＤＳＣ，ＷＡＸＤ，力学拉伸等手段对聚酯和聚氨酯进行了表征；讨论了软段聚酯的结构对聚氨酯的结晶性，耐热性，粘结性等性能的影响。     

Studies on the Cure Reaction and Relationship between Network Structure/Thermal Properties of Styrene Copolymers Based on Adypic/Sebacic Acid Modified Unsaturated (Epoxy) Polyesters

The studies on the relationship between network structure/thermal properties of styrene copolymers based on adypic/sebacic acid modified unsaturated (epoxy) polyesters cured using different hardeners as well as the course of the cure reaction of polyesters with styrene have been presented. The adypic/sebacic acid modified unsaturated polyesters (UP) prepared from 4-cyclohexene-1,2-dicarboxylic anhydride (THPA), maleic anhydride (MA), adypic acid (AA) or sebacic acid (SA) and ethylene glycol (EG) and their epoxy derivatives: adypic/sebacic acid modified unsaturated epoxy polyesters (UEP) were subjected to the cure process with styrene using diacyl peroxide: benzoyl peroxide (BPO) or the mixture of BPO/suitable acid anhydride: 4-cyclohexene-1,2-dicarboxylic anhydride (THPA) or glutaric anhydride (GA). Thermal properties were evaluated by means of DSC, TG and DMA analyses. It was proved that studied properties were significantly depended on polyester's structure and the type of applied curing system. Generally, higher values of E'_20°C, tgδ_max, E”, ν_e, IDT, T_k for styrene copolymers based on UEP were obtained. It was connected with more cross-linked polymer network structure due to the possible copolymerization reaction of carbon-carbon double bonds of polyester with styrene and additional polyaddition of epoxy to anhydride groups or thermal curing of epoxy groups. The additional connections between polyester's chains led to obtain more stiff and thermal stable polymeric materials. Moreover, the increase of saturated aliphatic acid's chain length in polyester backbone caused the decrease of E'_20°C, tgδ_max, E”, ν_e, IDT, T_k values of styrene copolymers. It suggested that copolymers based on polyesters prepared from acid containing more methylene groups in their structure were characterized by more flexible polymer network due to the “laxity” effect of aliphatic chains.     

生物可降解聚酯熔体的流变性质

采用毛细管流变仪,研究了PGA和PGLA910两种生物可降解聚酯熔体的流变性质。实验结果表明,两种聚合熔体均具有较低的剪切粘度,其非牛顿指数分别为:n_(PGA)=0.80-0.94,n_(PGLA910)=0.87-0.95;粘流活化能分别为:E_(PGA)=5.74-7.31kcal/mol,E_(PGLA910)=2.64-4.31kcal/mol。还采用“末端校正法”测定了两种聚合物熔体的剪切模量(G)和弹性可复形变(Sr),结果表明,PGLA熔体的弹性比PGA熔体大。     

多组分含金属透明树脂的结构与性能

研究了苯乙烯(St)、聚醚砜双烯大分子单体(PES-3-MA)、甲基丙烯酸铅[Pb(MA)_2]、桂皮酸钡[Ba(CA)_2]等多元共聚透明树脂的结构与性能的关系。实验结果表明:随PES-3-MA及Pb(MA)_2含量的增加,树脂的线膨胀系数α下降,树脂的密度却增大;间接求得D_(4P(PES-3-MA)~(20)=1.330、D_(4P(PSU-3-MA)~(20)=1.200、D_(4P[Pb(MA)_2]~(20)=2.100;PES-3-MA含量增加,树脂的硬度增大;Pb(MA)_2量增加,硬度下降;耐热性与不含Pb(MA)_2相比提高30～40℃。光声光谱研究表明悬吊双键需经较高温度的热处理才能进一步反应完全。     

Network Polymer Properties Engineered Through Polymer Backbone Dispersity and Structure

Dispersity (Ð or M_w/M_n) is an important parameter in material design and as such can significantly impact the properties of polymers. Here, polymer networks with independent control over the molecular weight and dispersity of the linear chains that form the material are developed. Using a RAFT polymerization approach, a library of polymers with dispersity ranging from 1.2—1.9 for backbone chain-length (DP) 100, and 1.4—3.1 for backbone chain-length 200 were developed and transformed to networks through post-polymerization crosslinking to form disulfide linkers. The tensile, swelling, and adhesive properties were explored, finding that both at DP 100 and DP 200 the swelling ratio, tensile strength, and extensibility were superior at intermediate dispersity (1.3—1.5 for DP 100 and 1.6—2.1 for DP 200) compared to materials with either substantially higher or lower dispersity. Furthermore, adhesive properties for materials with chains of intermediate dispersity at DP 200 revealed enhanced performance compared to the very low or high dispersity chains.     

尼龙11结构与性能的研究进展

结合作者的研究工作,综述了尼龙11的物理化学性质、晶体结构、晶型转变及压电性的研究进展。     

黄酮类化合物抗鼠肝微粒体脂质过氧化作用的结构与活性关系

黄酮类化合物具有多种药理作用 .由于该类化合物种类多 ,生物活性差别大 ,研究其抗氧化活性与结构的关系 ,将为寻找活性更强的黄酮类物质提供依据 .研究表明 [1] ,黄酮类化合物抗氧化活性与下列结构因素有关 :黄酮母核上的羟基数目及位置 ;B环上是否有邻二羟基 ;C环 2 ,3位是否有双键结构 ,4位是否有羰基结构 ;3 ,5位是否存在羟基 .由于不同研究者所研究的黄酮结构差异较大 ,目前所得到的抗氧化作用的构效关系并不十分一致 ,上述关系也不能全面概括黄酮类抗氧化作用的构效关系 .黄酮类化合物抗氧化活性不仅与其结构有关 ,还与氧自由基的种…     

Preparation,Crystal Structure,Physical Properties,and Electronic Band Structure of TlTaS3

TlTaS₃ was prepared by applying a sequence of two melting processes with mixtures of Tl₂S, Ta, and S having different molar metal to sulphur ratios. TlTaS₃ crystallises in space group Pnma with a = 9.228(3)Å, b = 3.5030(6)Å, c = 14.209(3)Å, V = 459.3(2)ų, Z = 4. The structure is closely related to the NH₄CdCl₃‐type. Characteristic features of the structure are chains of edge‐sharing [Ta(+5)S₄S_2/2]₂ double octahedra running along [010]. These columns are linked by Tl⁺ ions. The Tl⁺ ion is surrounded by eight S^2— anions to form a distorted bi‐capped trigonal prism. The Tl⁺ ions are shifted from the centre of the trigonal prism toward one of the rectangular faces. This is discussed in context with other isostructural compounds. TlTaS₃ is a semiconductor. The electronic structure is discussed on the base of band structure calculations performed within the framework of density functional theory.     

Studies on the Structure, Properties of Ferroaluminophosphate Molecular Sieve (FAPO-5) and Chemical State of Iron in the FAPO-5 Molecular Sieve

The pure Ferroaluminophosphate molecular sieve(FAPO-5) was synthesized by hydrothermal crystallization. The crystal structure of FAPO-5 was studied via XRD, electron probe energy dispersion analysis, Mossbauer spectroscopy, EPR, XPS and IR, the parameters of unit cell and chemical composition of FAPO-5 were determined. The result has that the structure of FAPO-5 is AlPO -5 type and Fe2+ Fe3+ are incorporated into the framework of FAPO-5 molecular sieve. In addition, the chemical state of iron in FAPO-5 molecular sieve were studied and the adsorption properties, surface acidity and thermal stability were also investigated.