Novel concept for low temperature curing powder coatings based on hyperbranched polyesters

The concept of using hyperbranched polymers as scaffolds for solid thermoset resin applications is de-scribed. A series of semi-crystalline methacrylate-functional aliphatic poly-esters has been synthesized and characterized for applications as solid thermoset resing, e.g., powder coating resins. The polyester resins have been crosslinked by UV irradiation producing either amorphous or semi-crystalline crosslinked films depending on the initial structure. The resins are based on hyperbranched aliphatic polyesters onto which crystalline linear aliphatic polyester chains have been grafted and end-capped with methacrylate moieties. The resins exhibit a rheological behavior suitable for low temperature curing powder coatings, i.e., films that can be readily formed and UV cured at temperatures below 80°C. Dept. of Polymer Technology, SE-100 44 Stockholm, Sweden. E-mails: matskg@polymer.kth.se. mave@polymer.kth.se, and andult@polymer.kth.se.     

Radiation curing of hyperbranched polyester resins

A research area that has obtained increasing interest during the last decade concerns improvement of macromolecular properties by changes in the macromolecular architecture. One group of these materials is dendritic polymers, which are highly branched structures exhibiting very different properties compared with linear polymers. One potential application for these polymers is as radiation curable thermoset resins. This article describes a study where the use of an aliphatic hyperbranched polyester as a base for new radiation curable thermoset resins. The hyperbranched polyesters have been characterized with respect to cure rate and final mechanical properties compared with conventional resins. It is shown that hyperbranched polyesters can be used as versatile scaffolds for various radiation curable resin structures. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 612–618, 2000     

采用超临界/亚临界水回收热固性树脂基复合材料

综述了近年来国内外研究者利用超临界/亚临界水分解热固性树脂基(如不饱和聚酯,酚醛树脂,环氧树脂等)复合材料的研究,该方法可将热固性树脂基复合材料分解为单体或低聚物,具有环保、经济、安全的特点,作为一种新兴技术,具有较好的发展前景。     

Effects of resin chemistry on redox polymerization of unsaturated polyester resins

Unsaturated polyester resins are the most widely used thermoset resins in the composite industry. In this study, three well‐defined unsaturated polyester resins were used. These resins have similar number‐average molecular weights, and they have different numbers of C?C bonds per molecule. The reaction kinetics of unsaturated polyester resins was studied using a differential scanning calorimeter (DSC) and a Fourier transform infrared (FTIR) spectrometer. The glass transition temperature of the isothermally cured resin was also measured. Trapped radicals were observed in the cured polyester resin from electron spin resonance (ESR) spectroscopy. Considering the diffusion‐limitation effect, a simple kinetic model was developed to simulate the reaction rate and conversion profiles of polyester vinylene and styrene vinyl groups, as well as the total reaction rate and conversion. Experimental results from DSC and FTIR measurements compare favorably with the model prediction. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 211–227, 2002; DOI 10.1002/app.10317     

4-叔丁基苯甲酸在聚酯树脂及其粉末涂料中的应用

采用对苯二甲酸、间苯二甲酸和新戊二醇为主体,控制单元羧酸4-叔丁基苯甲酸(PTBBA)的加量,合成了具有不同分子结构的聚酯树脂,研究了PTBBA对聚酯树脂及其异氰尿酸三缩水甘油酯(TGIC)和羟烷基酰胺(HAA)2种体系粉末涂料的影响规律,采用差式扫描量热仪(DSC)、凝胶色谱仪(GPC)、傅立叶变换红外光谱(FT-I...     

超支化环氧树脂的研究进展及应用前景

综述了各类超支化环氧树脂的合成工艺,主要包括聚酯型、聚醚型、聚酯聚醚型和聚烷烃超支化环氧树脂.超支化环氧树脂的合成工艺主要有缩水甘油直接法、环氧氯丙烷间接法、原子基团转移聚合法、双键加成法.对每种超支化环氧树脂的合成工艺、产品特征进行分析.提出了超支化环氧树脂在热固性材料、胶粘剂和作为无溶剂树脂等领域的应用前景.     

Comparison of unsaturated polyester and vinylester resins in low temperature polymerization

Many composite products are produced at low temperatures in processes such as resin transfer molding (RTM), vacuum infusion molding (e.g., Seemann Composite Resin Infusion Molding Process—SCRIMP), and hand lay‐up. These processes are widely used for marine, civil infrastructure, transportation and defense applications. Unsaturated polyester and vinylester resins are two major resins used in these processes due to their low cost, good performance, and processibility. In this study, the reaction kinetics and rheological changes of these two resins cured at low temperatures were studied. Effects of resin type, initiator, promoter, inhibitor and retarder on the reaction kinetics and rheological behaviors were examined using a Differential Scanning Calorimeter (DSC) and a Rheometrics Dynamic Analyzer (RDA). A model was developed to quantify the effects of resin type, temperature, and different curing agents on the gel time for both polyester and vinylester resins cured at low temperatures. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1230–1242, 2001     

衣康酸光固化树脂的研究进展

被誉为"绿色技术"的光固化技术,不仅节能环保而且经济高效,已在众多领域得以应用.利用天然可再生资源制备光固化树脂对光固化技术的可持续发展具有重要意义.衣康酸作为一种来源广泛的天然可再生资源,其分子结构中同时含有不饱和双键和两个羧基,可替代丙烯酸、己二酸等石化资源合成各种光固化不饱和树脂,所得树脂综合性能优良.本文综述了...     

Synthesis and characterization of bio‐based thermosetting resins from lactic acid and glycerol

A bio‐based thermoset resin has been synthesized from glycerol reacted with lactic acid oligomers of three different chain lengths (n): 3, 7, and 10. Lactic acid was first reacted with glycerol by direct condensation and the resulting branched molecule was then end‐functionalized with methacrylic anhydride. The resins were characterized by Fourier‐transform infrared spectroscopy (FT‐IR), by ¹³C‐NMR spectroscopy to confirm the chemical structure of the resin, and by differential scanning calorimetry and dynamic mechanical thermal analysis (DMTA) to obtain the thermal properties. The resin flow viscosities were also measured using a rheometer with different stress levels for each temperature used, as this is an important characteristic of resins that are intended to be used as a matrix in composite applications. The resin with a chain length of three had better mechanical, thermal, and rheological properties than the resins with chain lengths of seven and 10. Also, its bio‐based content of 78% and glass transition temperature of 97°C makes this resin comparable to commercial unsaturated polyester resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40488.     

星形支化树脂在紫外光固化粉末涂料中的应用

用可紫外光固化的星形支化树脂作主要成膜物,制成了紫外光固化粉末涂料。讨论了星形支化树脂用量对光固化粉末涂料熔融黏度、漆膜光泽度、鲜映性、耐溶剂擦洗性的影响,考察了紫外光固化粉末涂料熔融黏度随温度的变化,以及漆膜的玻璃化温度与光照时间的关系。结果表明,与紫外光固化线性树脂相比,星形支化树脂应用于粉末涂料中时,可制得熔融黏度更低、漆膜外观更好、漆膜耐溶剂性更优的紫外光固化粉末涂料。     

固化促进剂在耐候粉末涂料用聚酯树脂中的应用研究

研究了耐候粉末涂料用聚酯树脂合成中固化促进剂的作用;讨论了固化促进剂的选择、加入量、加入时机对树脂性能及涂层固化性能的影响;分析了固化促进剂对不同配方聚酯合成的影响。     

Chemical approaches toward the definition of new high-solid and high-performance fluorocoatings

Hydroxy bifunctional fluoropolyether oligomers (ZDOL) are presented suitable for use as resins or for the preparation of polyurethane, polyester and polyether higher OH functionality resins. The synthesis procedures are described and discussed, and the effect of fluorine content and resin structure on glass transition temperature T_g and viscosity of final resin is stressed. It appears that the highly fluorinated polyether type resins, like the tetraolic derivative (TOL) and its mixtures with ZDOL, are characterized by only one, extremely low T_g and minimum viscosity values. Solvent–resin interactions and criteria for obtaining compatibility with polyisocyanate crosslinkers are discussed, pointing out the key role of hydrogen bonding. High solid coatings (solvent content less than 30%) are obtained by curing with blocked aliphatic polyisocyanates, and a preliminary characterization of final materials based on their thermal transitions and mechanical properties is reported.     

Structure and properties of o-carboxymaleanilic polyester resins

Polyester resins were prepared by the reaction of o-carboxymaleanilic acid with ethylene trimethylene, propylene, hexamethylene, diethylene, or 1,4-butenediol. All the polyester resins obtained have been characterized and were found to cure with styrene, except the polyester from diethylene glycol. The properties of the cured products in the form of films were determined. Infrared. UV, and NMR spectroscopy were used for both qualitative and quantitative analyses of the polyester resins and their hydrolyzate products, after curing with styrene.     

Cure of secondary carbamate groups by melamine-formaldehyde resins

Melamine-formaldehyde (MF) resins have been used as crosslinkers for hydroxyl-functional coreactants in thermoset coatings for about 60 years. Crosslink densities of films prepared from oligomeric urethane polyols suggested that the methoxymethyl groups of MF resins could react with urethane groups (i.e., secondary carbamate groups) as well as reacting with hydroxyl groups. Co-reactants that contain secondary carbamate groups and no hydroxyl groups have been prepared with several types of backbone structures. Cure of such co-reactants by MF resins has been studied using a gradient oven with determination of impact resistance, solvent resistance, and hardness. Several formulations from these cure profile sets have been selected for crosslink density determinations by dynamic mechanical analysis (DMA). Crosslink densities of cured films are consistent with complete conversion of secondary carbamate groups at temperatures only slightly higher than those used for cure of hydroxyl groups. The -OH groups on certain acrylic polyols were converted to secondary carbamate groups. The original acrylic and the converted acrylic were both cured with MF resins. Acid resistance was much better for films prepared from the acrylic that contained secondary carbamate groups. Presented at the 25th International Waterborne, High-Solids, and Powder Coating Symposium, New Orleans, LA, Feb. 18–20, 1998. 730 Worcester Street, Springfield, MA 01151.     

1999—2000年我国塑料工业进展

介绍了1999－2000年我国塑料工业进展。根据1999年7月－2000年6月期间国内合成树脂及塑料工业及相关学科的原始文献资料,对通用热塑性树脂（聚乙烯、聚丙烯、聚氯乙烯、聚苯惭烯及ABS）、热固性树脂（酚醛、环氧、聚氨酯、不饱和聚酯、双马来酰亚胺）、工程塑料（尼龙、聚碳酸酯、聚甲醛、热塑性聚酯及PPO）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮、聚砚聚醚砚、其它和特种工程塑料）、其它树脂（聚酰亚胺、有机硅、有机氟树脂、丙烯酸树脂、降解塑料、吸水吸油树脂及功能树脂）、成型加工与设备、塑料助剂和应用开发等各专业领域国内环境、发表的论文、取得的成果和工艺、技术进步作了全面、系统的介绍,展示了我国1999－2000年合成树脂和塑料工业的进展。     

The development of canola oil based bio‐resins

Bio‐based resins made from vegetable oils offer a sustainable alternative to petroleum‐based thermoset resins. The thermosetting resin systems we have developed from epoxidized canola oil and the polyurethanes we have produced from canola oil‐based polyols show promise as cost‐effective materials incorporating a high renewable content. Here we outline the use of canola oil based bio‐resins in composite boards, and in polyurethane adhesive and insulating foam applications.     

不饱和聚酯型人造石英石的紫外老化研究

对不饱和聚酯树脂粘合的人造石英石板材进行了人工紫外加速老化试验,通过显微观察其表面形态,比较色差值,并采用红外谱图分析,研究石英石板材的紫外老化情况。试验结果表明,四种类型的不饱和聚酯树脂石英石在经过500h紫外照射后,表层都会出现不同程度的粉化现象。而FTIR谱图显示,树脂并没有出现明显的链降解,石英石板面的粉化应是石英粉与树脂的接合面在老化试验中发生分离,导致石英粉脱落。     

2010～2011年世界塑料工业进展

收集了2010年7月～2011年6月世界塑料工业的相关资料,介绍了2010～2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

羟基聚酯树脂的合成及其在美术型粉末涂料中的应用

介绍了一种粉末涂料用端羟基聚酯树脂的合成,用差热分析仪(DTA)分析了聚酯树脂的玻璃化转变温度(Tg),测试了树脂酸值、羟值和熔融黏度等理化指标;由聚酯树脂制成皱纹、龟纹等美术型粉末涂料,讨论了羟值和单体对羟基聚酯合成皱纹粉末涂料纹理效果的影响;讨论了不同粉末涂料配方对龟纹粉末涂料纹理效果的影响;测试了聚酯树脂粉末涂料...     

LCD用UV固化胶黏剂的研制

以聚酯多元醇、二异氰酸酯和丙烯酸羟乙酯为原料,合成聚氨酯丙烯酸预聚体,并在此基础上通过添加活性稀释单体、光引发剂等配制成UV固化胶黏剂。通过分析不同组分在LCD液晶灌注口密封及金属管脚固定的粘接性能影响,确定合成预聚体所需的聚酯多元醇种类及丙烯酸羟乙酯的合适用量,同时确定配胶所需活性稀释单体与光引发剂的合适用量。最后制得粘接性能好、耐候性能佳,可满足LCD产品生产工艺的性能要求的UV固化胶黏剂。