我国双环戊二烯改性不饱和聚酯树脂的研究进展

综述了双环戊二烯改性不饱和聚酯树脂的生产技术,重点介绍了我国近年来双环戊二烯改性不饱和聚酯树脂的研究进展,并指出了双环戊二烯改性不饱和聚酯树脂的发展方向。     

不饱和聚酯树脂改性研究进展

不饱和聚醣树脂是一种重要的热固性聚脂,在工业、农业、交通、建筑等方面得到广泛应用。文章综述了不饱和聚酯树脂改性研究的最新进展,重点介绍了不饱和聚酯低固化收缩率、阻燃、增强增韧、耐热、耐介质、气干性的改性研究方法,并指出了不饱和聚酯树脂改性中存在的问题和发展方向。     

有机累托石改性不饱和聚酯／玻璃纤维复合材料的研究

采用有机累托石改性不饱和聚酯，以改性的不饱和聚酯为基体，以两种玻璃布(EW210、CWR400-90)为增强材料，以两个不同凝胶时间的不饱和聚酯树脂体系制备三种有机累托石改性的不饱和聚酯磁璃纤维复合材料(UPB1、UPB2、UPB3)。测试了不饱和聚酯/玻璃纤维的力学性能；研究了复合材料的耐湿热性及耐介质性能；利用扫描电镜及透射电镜分析了复合材料的增强机理。结果表明，采用有机累托石改性不饱和聚酯所制备的不饱和聚酯／玻璃纤维复合材料的综合力学性能优于纯不饱和聚酯／玻璃纤维复合材料。     

不饱和橡胶环氧化改性的研究进展

综述国内外常用的有机过氧酸法、过硫酸氢钾复合盐/丙酮法和过渡金属催化剂/过氧化氢法环氧化改性不饱和橡胶的研究进展,重点分析不饱和橡胶环氧化反应的机理;概述不饱和橡胶各种环氧化改性方法的优缺点;指出未来会继续重视环境友好型不饱和橡胶环氧化改性方法及高效、低廉、可再利用催化剂等的研究。     

改性松香不饱和聚酯树脂的研究

本文以来源丰富、廉价的松香与丙烯酸反应制得改性松香来代替邻苯二甲酸酐合成改性松香不饱和聚酯树酯,并对其性能作了研究.通过试验表明:改性松香不饱和聚酯树脂比之通用型不饱和聚酯树脂固化时放热温度低,其力学性能韧性与对断裂低抗能力大为增加,达到了改性与降低原料成本目的.研究还表明:改性松香不饱和聚酯树脂比之通用型不饱和聚酯树脂的玻璃化温度有所提高,有利于其成型加工,扩大了应用范围.     

丙烯酸酯改性不饱和聚酯的研究

普通不饱和聚酯树脂脆性大,故有必要对其进行增韧改性。本文合理选用丙烯酸酯对不饱和聚酯树脂进行增韧及其他性能改性,制备改性不饱和聚酯树脂。研究表明,随着丙烯酸丁酯（BA）的用量增加,不饱和聚酯的断裂伸长率、冲击强度增加;但不饱和树脂的弹性模量减小、拉伸强度急剧降低,当BA的用量为10%时,弹性模量减少至1.0 GPa左右;耐水分析表明树脂的耐水性能优良;DSC差热分析表明,改性树脂的Tg值在61℃左右,满足基本的使用要求。     

HTPB引入方式对不饱和树脂改性效果的影响

以高顺式端羟基液体顺丁橡胶（HTPB）为改性剂,分别采用共混-共固化法、共缩聚法制备了共混改性型不饱和聚酯[UPR+HTPB(blend)]、无规共缩聚改性型不饱和聚酯（UPR-HTPB）和嵌段共缩聚改性型不饱和聚酯（UPR-MAH-HTPB）,系统地考察了三种改性不饱和聚酯固化样品的机械物理性能。结果表明,三种改性不饱和树脂的断裂伸长率、拉伸强度和冲击强度均优于未改性的不饱和树脂,固化收缩率大幅降低,且共缩聚改性树脂（UPR-HTPB和UPR-MAH-HTPB）的增韧效果和降收缩效果明显优于共混改性树脂。此外,UPRMAH-HTPB的拉伸模量也优于未改性的不饱和树脂,硬度和热变形温度则基本保持不变。冲击断面的形貌、交联密度和DMA分析表明,UPR+HTPB(blend)固化体系中存在着HTPB聚团的现象,而共缩聚改性树脂,尤其是嵌段型的UPR-MAH-HTPB,因HTPB嵌入到UPR的主链中,使HTPB微相分离,并更多地参与交联,在增韧的同时保持了树脂良好的刚性和强度。     

α-亚麻酸改性的新型耐湿热树脂的研制

不饱和聚酯树脂耐湿热性能较差的缺陷影响了其应用领域及使用寿命，用α-亚麻酸可对不饱和聚酯进行改性，研究了反应时间、温度及改性剂掺量对不饱和聚酯耐湿热老化性能的影响，进行了改性与未改性不饱和聚酯耐湿热性能的比较，同时用红外光谱图（IR）对其反应效果进行了微观分析。实验结果表明：亚麻酸对不饱和聚酯的改性极大地提高了其耐湿热老化性能。     

聚氨酯改性不饱和聚酯树脂的制备

利用二步法由二元醇、二元酸及TDI合成一种聚氨酯改性不饱和聚酯树脂,第一步由二元醇和二元酸合成以羟基封端的不饱和聚酯,第二步利用不饱和聚酯的—OH与TDI的—NCO反应合成聚氨酯改性不饱和聚酯,使得树脂分子链段上既有不饱和链节又含有聚氨酯基团,结合了聚氨酯涂料和不饱和聚酯涂料的优点,使其涂膜性能优异。试验发现TDI加入量为10%时效果最佳。     

植物纤维改性不饱和聚酯复合材料研究进展

概述了木纤维、麻纤维、棕榈纤维以及其它植物纤维改性不饱和聚酯复合材料的研究进展及其应用领域。并对植物纤维改性不饱和聚酯复合材料的发展方向进行了展望。     

Properties and Aggregate Structure of Unsaturated Polyester/Phenolic Resin Blends

In this study, unsaturated polyester resin (UP) is blended with resole type phenolic resin, co-crosslinking process performed and the resin blends show miscibility and interpenetration network (IPN) structure. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) are employed to examine the aggregate structure of crosslinked network of the UP/phenolic resin blend. Tensile fractured sections of the resin blends are observed using scanning electronic microscopy (SEM) to shed light on their miscibility. Tensile and flexural tests were also conducted to examine the mechanical properties of the UP/phenolic resin blends. The results show that UP20/Ph80 and UP40/Ph60 resin blends have well-formed Interpenetrating Network (IPN) structures while phase separation is observed for UP60/Ph40 resin blend. Finally, thermal cure of UP80/Ph20 resin blend is incomplete, thus showing immiscibility. The mechanical properties of all resin blends at different mixing proportions deviate from a linear relationship and show a concave curve, indicating the non-additive effect of blending.     

Thermal cure behavior of unsaturated polyester/phenol blends

Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were used to detect and simulate the cure behavior of unsaturated polyester (UP), phenol, and UP/phenol blends and to calculate and predict the cure rate, cure temperature, conversion, and changes in the glass‐transition temperature along with various cure orders in order to obtain the optimum parameters for processing. With dynamic scanning and isothermal DSC procedures and Borchardt–Daniels dynamic software, cure data for the UP resin were obtained, 90% of the conversion rate at 100°C being achieved after 15 min. However, for the phenol and UP/phenol blends, gradually increasing the temperature was found to be best for curing according to the DSC and DMA test results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1041–1058, 2004     

The preparation and physical properties of UP/montmorillonite nanocomposite by UV radiation curing

This article describes the preparation and properties of unsaturated polyester (UP)/montmorillonite (MMT) nanocomposite by UV radiation. Benzildimethylketal and 1‐hydroxy cyclohexyl phenyl ketone (HCPK) as a photoinitiator in UP were photolyzed under nitrogen condition. Analysis of X‐ray diffraction patterns of the composites shows that the interlayer spacing of MMT is substantially increased. The type and amount of photoinitiator affects the level of improvement in mechanical properties, and our results suggest that HCPK is a more efficient photoinitiator of UP curing reaction. The interaction between photoinitiators and MMT should be considered to acquire the reinforcement effect of the dispersed MMT nanolayers. The properties of nanocomposite are dependent upon the amount of MMT. The effect of MMT concentration on thermal and dielectric properties is also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3609–3615, 2006     

Mechanical characterization and chemical resistances of cured unsaturated polyester resins modified with vinyl ester resins based on recycled poly(ethylene terephthalate)

Unsaturated polyester resin (UP) was prepared from glycolyzed oligomer of poly(ethylene terephthalate) (PET) waste based on diethylene glycol (DEG). New diacrylate and dimethacrylate vinyl ester resins prepared from glycolysis of PET with tetraethylene glycol were blended with UP to study the mechanical characteristics of the cured UP. The vinyl ester resins were used as crosslinking agents for unsaturated polyester resin diluted with styrene, using free‐radical initiator and accelerator. The mechanical properties of the cured UP resins were evaluated. The compressive properties of the cured UP/styrene resins in the presence of different vinyl ester concentrations were evaluated. Increasing the vinyl ester content led to a pronounced improvement in the compression strength. The chemical resistances of the cured resins were evaluated through hot water, solvents, acid, and alkali resistance measurements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3175–3182, 2007     

Effects of reactive low‐profile additives on the volume shrinkage and internal pigmentability for low‐temperature cure of unsaturated polyester

The effects of reactive poly(vinyl acetate)‐block‐poly(methyl methacrylate) (PVAc‐b‐PMMA) and poly(vinyl acetate)‐block‐polystyrene (PVAc‐b‐PS) as low‐profile additives (LPA) on the volume shrinkage characteristics and internal pigmentability for low‐shrink unsaturated polyester resins (UP) during the cure at 30°C were investigated. These reactive LPAs, which contained peroxide linkages in their backbones, were synthesized by suspension polymerizations, using polymeric peroxides (PPO) as initiators. Depending on the LPA composition and molecular weight, the reactive LPA could lead to a reduction of cyclization reaction for UP resin during the cure, and would be favorable for the decrease of intrinsic polymerization shrinkage after the cure. The experimental results have been explained by an integrated approach of measurements for the static phase characteristics of the styrene (ST)/UP/LPA system, reaction kinetics, cured sample morphology, and microvoid formation by using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), optical microscopy (OM), and image analysis. Based on the Takayanagi mechanical model, factors leading to both a good volume shrinkage control and acceptable internal pigmentability for the molded parts have been explored. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 967–979, 2006     

阻燃剂对UP复合材料流变性及磨损性能的影响

制备了含有氢氧化铝(ATH)、三聚氰胺多聚磷酸盐(MPP)及十溴二苯醚(DBDE)等不同阻燃剂的干式不饱和聚酯/玻璃纤维(UP/GF)共混复合材料。研究了不同阻燃剂对UP/GF复合材料的阻燃性能、流动性和磨损性能的影响,并借助SEM观察了采用不同阻燃剂的UP/GF复合材料的磨损面微观形貌。结果表明,ATH的添加质量为30%时,其UP/GF复合材料的阻燃性与DBDE添加量为25%的体系相当,达到UL94 V-0级,OLI值为30.0且具有很好的抑烟和防滴落效果;同时ATH、MPP的加入可适当提高复合材料流动性能,ATH还可以改善复合材料的磨损性能,磨损体积为未添加阻燃剂体系的50%左右。     

活性端基聚氨酯橡胶改性不饱和聚酯树脂的研究(Ⅱ)

通过在不饱和聚酯树脂中加入活性端基聚氨酯橡胶来降低树脂的体积收缩.树脂固化前,橡胶与不饱和聚酯树脂相溶性好;树脂固化时橡胶中的不饱和双键反应可参与反应,并呈一定粒径的胶粒析出.本文研究了几种活性端基聚氨酯橡胶对不饱和聚酯树脂收缩控制的影响.     

氢氧化铝含量对聚酯/玻璃纤维复合材料阻燃性能和力学性能的影响

通过熔融混炼和模压成型工艺,制备含氢氧化铝(ATH)的干式不饱和聚酯/玻璃纤维(UP/GF)共混复合材料。采用氧指数法(LOI)和垂直燃烧法(UL94)表征UP/GF复合材料的阻燃性能,采用DMA研究UP/GF复合材料的动态力学性能,采用静态力学方法研究UP/GF复合材料的冲击和弯曲性能。结果表明:UP复合材料中,ATH的含量在25%时,既能够满足V—0级阻燃级别,氧指数值为28.7%,且材料的冲击和弯曲强度分别为5.66kJ/m2和58.72MPa,同时也有较好的动态力学性能。     

不饱和聚酯和环氧树脂嵌段共聚物的研究

本文利用环氧基功能团与羟基反应,使聚酯分子扩链,合成了A—B—A型嵌段共取物,其耐酸碱性比普通型不饱和聚酯强可与3301双酚A型不饱和聚酯媲美,提高了聚酯的耐碱性。     

Unsaturated polyester–poly(ε‐caprolactone) hybrid nanocomposites: Thermal–mechanical properties

This paper reports on the thermal behavior and mechanical properties of nanocomposites based on unsaturated polyester resin (UP) modified with poly(ɛ‐caprolactone) (PCL) and reinforced with an organically modified clay (cloisite 30B). To optimize the dispersion of 30B and the mixing of PCL in the UP resin, two different methods were employed to prepare crosslinked UP–PCL‐30B hybrid nanocomposites. Besides, two samples of poly(ɛ‐caprolactone) of different molecular weight (PCL2: M_n = 2.10³g.mol⁻¹ and PCL50: M_n = 5.10⁴g.mol⁻¹) were used at several concentrations (4, 6, 10 wt%). The 30B concentration was 4 wt% in all the nanocomposites. The morphology of the samples was studied by scanning electron microscopy (SEM). The analysis of X‐ray patterns reveals that intercalated structures have been found for all ternary nanocomposites, independently of the molecular weight, PCL concentration and the preparation method selected. A slight rise of the glass transition temperature, T_g, is observed in UP/PCL/4%30B ternary nanocomposites regarding to neat UP. The analysis of the tensile properties of the ternary (hybrid) systems indicates that UP/4%PCL2/4%30B nanocomposite improves the tensile strength and elongation at break respect to the neat UP while the Young modulus remains constant. POLYM. COMPOS., 35:827–838, 2014. © 2013 Society of Plastics Engineers