LDPE 高透明专用树脂的开发

探讨了高透明低密度聚乙烯(LDPE)专用树脂25E的生产工艺条件,分析了反应压力、反应温度、相对分子质量调节剂及引发剂的用量对高透明LDPE树脂性能的影响,最终确定了反应温度为(315±5)℃、反应压力为(255±5)MPa、调节剂丙醛注入量为20~30kg/h等生产工艺参数,并对产品进行了基础物性和加工性能分析。加工应用试验表明,25E产品的综合性能优良,达到了国内同类产品的先进水平。     

消光PVC专用树脂的合成研究

通过氯乙烯／交联剂悬浮聚合合成了含有部分凝胶结构的消光PVC专用树脂，讨论了交联剂，联合温度，分散剂及引发剂等对消光性能的影响，并初步分析了树脂的加工性能。     

基于光敏水溶性树脂的耐高温涂料配方及成膜工艺研究

以多羧基酚醛光敏树脂为基本原材料制备了能完全水溶性的、可光交联且交联后耐高温的特种涂料,考察了多羧基酚醛光敏树脂与添加剂的比例关系以及最佳配方、成膜工艺条件。当涂料中多羧基酚醛光敏树脂的质量分数为23 4%、乙基-对-二甲基胺基苯甲酸酯(EDAB)和异丙基硫杂蒽酮(ITX)为0 23%[m(EDAB)∶m(ITX)=2]、三羟甲基丙烷三丙烯酸酯(TMP TA)为6 9%、氨水为1 0%、丙烯酰胺为1 56%、丙酮为39 8%、水为27 1%时,漆膜在50℃下真空预处理2h,紫外光交联30s,热后处理1h后,所得漆膜具有优良的耐酸碱性、耐溶剂性,附着力为1级,在280℃的导热油中30s无变化。     

Fabrication and microstructure development of Yb:YAG transparent ceramics from co-precipitated powders without additives

Sintering additives are generally considered to be important for improving densification in fabrication of transparent ceramics. However, the sintering aids as impurities doped in the laser materials would decrease the laser output power and produce additional heat during laser operation. In this work, Yb:YAG ceramics were vacuum-sintered without additives at different temperatures for various soaking time through using ball-milled powders synthesized by co-precipitation route. The densification behavior and grain growth kinetics of Yb:YAG ceramics were systematically investigated through densification curves and microstructural characterizations. It was determined that the densification in the 1500°C-1600°C temperature range was controlled by a grain-boundary diffusion. It is revealed that the volume diffusion is the main mechanism controlling the grain growth between 1600°C and 1750°C. Although SiO₂ additives can promote densification during low-temperature sintering, the optical transmittance of Yb:YAG ceramic with no additives, sintered at 1800°C for 15 hours, reaches a maximum of 83.4% at 1064 nm, very close to the measured transmittance value of Yb:YAG single crystal. The optical attenuation loss was measured at 1064 nm in Yb:YAG transparent ceramic, to be 0.0035 cm⁻¹, a value close to that observed for single crystals.     

二元共聚高吸油树脂的合成工艺

以甲基丙烯酸丁酯及苯乙烯为主要单体、丙二醇二丙烯酸酯为交联剂、偶氮二异丁腈为引发剂,采用悬浮聚合方法,合成一种白色颗粒状的共聚型高吸油树脂。考察了搅拌速率、分散剂浓度、聚合温度、单体配比、交联剂用量等因素对颗粒特性的影响。研究结果表明,当共聚单体配比(质量比)为1.6∶1、分散剂水溶液浓度为0.1%～0.2%、交联剂用量为单体质量的1%、搅拌转速200～300 r/min、聚合温度70℃、聚合时间为6h时,合成出的树脂粒径适中,吸油倍率达到20倍。     

透明高抗冲聚苯乙烯树脂的工业化试验

在5kt／a高抗冲聚苯乙烯树脂装置上,以1,1-双(叔丁基过氧基)环己烷为引发剂、苯乙烯为单体、丁二烯-苯乙烯嵌段共聚物(简称K树脂)为增韧剂,采用自由基聚合工艺生产了透明高抗冲聚苯乙烯(HT-IPS)树脂,考察了HT-IPS树脂的微观结构、相对分子质量及其分布、流变性能、接枝反应程度、物理机械性能和光学性能,讨论了影响HT-IPS树脂结构及性能的因素。结果表明,HT-IPS树脂具有微观相分离结构,聚丁二烯链段为分散相、聚苯乙烯链段为连续相;HT-IPS树脂的流动性能略差于高抗冲聚苯乙烯树脂,且随着K树脂用量的增加,其流动性能变差,K树脂用量应控制在15份以下;在聚丁二烯链段的主链和侧链均发生了接枝反应,HT-IPS树脂具有较高的弯曲强度、弹性模量和拉伸强度,其光学性能、流变性能良好,但冲击强度较低,扯断伸长率较小。     

橡胶粒子粒径对ABS树脂结构与性能的影响

采用乳液技术在聚丁二烯(PB)和丁苯橡胶(SBR)乳胶粒子上接枝共聚苯乙烯和丙烯腈合成了PB质量分数为60％的ABS接枝粉料,将其与苯乙烯-丙烯腈共聚物(SAN树脂)熔融共混获得了一系列不同组成和结构的丙烯腈-丁二烯-苯乙烯共聚物(ABS树脂),研究了橡胶粒子粒径对ABS树脂的形态结构、力学性能的影响.结果表明,PB和SBR橡胶粒子的粒径分别为0.3μm和0.05 μm左右时,橡胶粒子的粒径对ABS树脂力学性能的影响十分显著.单独采用小拉径SBR橡胶粒子不能有效地增韧SAN树脂,而大粒径PB橡胶粒子对SAN树脂具有良好的增韧效果.     

本体聚合ABS树脂技术进展

综述了国内外主要本体聚合丙烯腈-丁二烯-苯乙烯(ABS)树脂生产工艺,分析了各工艺的技术特点及其成熟度,总结了本体聚合工艺中的关键技术(如ABS树脂性能的影响因素和橡胶粒径的控制方法等)。本体法是最佳的ABS树脂生产工艺,正成为研究重点。本体聚合ABS树脂工艺的研究方向:调整工艺配方、加入第三单体改性、将本体ABS树脂与乳液接枝-掺混法获得的ABS树脂共混制备高性能的ABS树脂新产品。     

C_9热聚石油树脂的研究

以裂解C9中双环戊二烯含量较多的馏分为原料,与裂解C9切出的轻组分按一定比例混合,在一定温度和压力下通过热聚合得到热聚石油树脂。研究了反应温度、反应时间及不同原料配比对树脂性能的影响,确定了适宜的聚合温度、压力、反应时间等工艺条件,制得软化点大于130℃,色度7以下的高品质石油树脂。     

交联剂对合成高吸油性树脂的影响

采用水分散相悬浮聚合法，以甲基丙烯酸长链烷基酯为单体，二甲基丙烯酸乙二醇酯为交联剂合成高吸油性树脂；并且探讨了交联剂对聚合过程和树脂吸油性能的影响。实验证明，交联剂用量越大，体系凝胶化现象到来得越早，转化率随反应时间增长得较快，但是最终转化率相差不大。交联剂用量越大，树脂对各种油品的吸油倍率越小；交联剂的用量大于0.4mL时，吸油倍率变化不明显。     

药用渗透型树脂尤特奇RL合成工艺研究

甲基丙烯酸甲酯、丙烯酸乙酯、甲基丙烯酸氯化三甲胺基乙酯为原料,偶氮二异丁酸二甲酯为引发剂,采用分段聚合的方法,制备药用渗透型丙烯酸树脂尤特奇RL。以结构表征和理化性能试验,考察聚合方法的可行性。     

Microstructural changes of phenolic resin during pyrolysis

After curing, phenol‐formaldehyde resins were postcured at 230°C in air for 32 h and then carbonized and graphitized from 300 to 2400°C. Thermal fragmentation and condensation of the polymer structure occurred above 300°C. The crystal size of the cured phenolic resins decreased with the temperature increase. Above 600°C the original resin structures disappeared completely. Below 1000°C the stack size (L_c) and crystal size (L_a) were small. Above 1000°C the L_c increased with the increasing treatment temperature. The carbonized and graphitized resins were characterized using Raman spectroscopy. Below 400°C there were no carbon structures in the Raman spectra analysis. Above 500°C the G and D bands appeared. The frequency of the G band of all carbonized and graphitized samples shifted to 1600 cm^?1 from the 1582 cm^?1 of graphite. The D band shifted to 1330 cm^?1 from the 1357 cm^?1 of the imperfect carbon. The carbonized and graphitized phenolic resins could not be considered as truly glassy or amorphous carbon materials because they had some degree of order in the basal plane. However, the crystal size was very small even at 2400°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1084–1089, 2001     

丙烯酸酯系共聚物高吸油树脂的合成及性能研究

以甲基丙烯酸十八酯（SMA）、丙烯酸丁酯（BA）和苯乙烯（St）为单体，二乙烯苯（DVB）为交联剂，过氧化苯甲酰（BPO）作引发剂，采用悬浮聚合法合成高吸油性树脂。以吸油率作为性能指标，利用正交试验分析各种反应因素对树脂吸油率的影响，得出最佳工艺条件，并系统研究了体系中单体组成及配比、交联剂、引发荆、分散剂及致孔剂用量等因素对吸油树脂性能的影响。结果表明，当m（SMA）：m（BA）：m（St）=42：58：8，ω（BPO）=1.0％，ω（DVB）=1．2％，ω（PVA）=0．2％，ω（CHCl3）=10％时，树脂吸油率达到最大，可吸收四氯化碳23．61g／g，甲苯22．58g／g，笨18．85g／g，柴油14.8g／g。树脂的保油率在90％以上。经过热重分析可知，树脂的稳定性比较好，分解温度在333．7℃。     

小本体聚丙烯纤维级树脂开发初探

论述了开发小本体聚丙烯纤维级树脂的必要性;通过纺丝试验和分析研究,阐明了开发纤维级树脂的可行性;指出了提高小本体聚丙烯质量开发纤维级产品的几点意见。认为采用高效载体催化剂、进行物理化学改性和开发连续化工艺,可提高树脂熔体流动速率、减小分子量分布、降低灰分和其他有害杂质含量、改善可纺性和纤维质量,是开发小本体纤维级树脂的有效途径。     

Synthesis and characterization of glycerol dimethacrylate cross-linked polymethyl methacrylate: a resin for solid phase peptide synthesis

The new glycerol dimethacrylate cross-linked polymethyl methacrylate polymer support (GDMA-PMMA) for solid phase synthesis is presented. The synthesis of GDMA-PMMA resin is based on the cross-linking of GDMA with methyl methacrylate by free radical polymerization, affording a polymer containing ester and secondary hydroxyl groups. The polymer was prepared using benzoyl peroxide as initiator either via bulk polymerization or via suspension polymerization in polyvinyl alcohol, the latter yielding a beaded resin. The polymerization reaction was investigated with respect to the effect of amount of cross-linking agent in order to vary the swelling, loading and the mechanical stability of the resin. The polymer was characterized by FT-IR and ¹³C CP MAS NMR spectroscopic techniques. The solvent uptake of the polymer was studied in relation to cross-linking and compared with Merrifield resin. The stability of the resin was tested in various synthetic conditions used in solid phase peptide synthesis. The resin was derivatized with chloro and amino functional groups. The C-terminal amino acid incorporation, Nα-Fmoc deprotection, acylation reactions and removal of target peptide from the support were optimized. The efficiency of the resin was demonstrated by synthesizing leucyl-alanyl-glycil-valine, alanine-alanine-alanine-alanine, acyl carrier protein (65-74) and retro-acyl carrier protein (74-65) fragments under optimal conditions and is compared with Merrifield resin. The purity of the peptides was checked by HPLC and identities were established by amino acid analysis and mass spectroscopic techniques.     

星型嵌段共聚丁苯抗冲透明树脂的合成

研究了以丁基锂为引发剂,以环乙烷溶剂中合成抗冲及透明性颇佳的星型丁二烯－苯乙烯共聚嵌段树脂（简称为ITPS）主要的影响因素。结果表明以正丁基锂为引发剂制备的ITPS透明性好;偶合剂用甲基三甲氧基硅烷可以达到偶合效率、力学性能及透明性三者兼顾;m（丁二烯）／m（苯乙烯）＝20／80所合成ITPS的各项性能最佳;四氢呋喃的加入使聚丁二烯分子链段中的1,4－结构明显减少,1,2－结构增加,且ITPS的弯曲强度与其用量成正比;后处理方式和组合防老剂可以分别使ITPS透光率提高16．6％及11．1％。     

不饱和聚酯树脂微乳液的研究(Ⅱ)不饱和聚酯树脂微乳液聚合

磺酸盐不饱和聚酯和丙烯酸乙酯形成的微乳液用过硫酸钾或辐射引发共聚合,用膨胀计法测定聚合速率随转化率的变化,发现用过硫酸钾热引发存在聚合恒速期,恒速期随引发剂含量的减小或聚酯/丙烯酸乙酯质量比增大而变长。60Co-γ辐射引发几乎无恒速期。动态光散射法测定微乳液粒径的大小,发现聚合后的流体力学直径比聚合前都大,过硫酸钾引发胶乳流体力学直径比辐射引发胶乳流体力学直径大,同时对聚合机理进行了讨论。     

PVC糊树脂的结构性能研究

通过对不同工艺PVC糊树脂的微观结构、粒径分布、凝胶化过程、脱膜性能的研究，确定了微悬浮和种子乳液法糊树脂的特性。     

影响丙烯酸树脂粘度的工艺研究

在涂料用丙烯酸酯树脂的合成中,通过研究不同引发剂在不同工艺条件下对树脂产物的影响,以及不同溶剂对树脂的溶解性能,为生产实践中设计和控制树脂粘度寻找了一些方法,也为制作某些特性树脂而选用合成工艺、引发剂和溶剂提供了思路。     

甲基丙烯酸高碳链混合醇酯合成及制备吸油树脂的研究

用正交试验法考察了甲基丙烯酸和高碳链混合醇直接酯化合成甲基丙烯酸混合醇酯的工艺条件。其酯化反应的工艺条件为：酸醇量比为1.2：1,w（催化剂）为1.5%,w（阻聚剂）为0.5%,反应温度130℃,反应时间4h,空气流速为0.16L/min。用甲基丙烯酸高碳链醇酯为单体,1,4-丁二醇二丙烯酸酯为交联剂,过氧化苯甲酰为引发剂,聚乙烯醇为分散剂,采用分散聚合法制备了具有吸油性能的甲基丙烯酸高碳链混合醇酯共聚树脂,并用均匀设计试验法优化了聚合合成工艺条件：w（交联剂）为1.2956%,w（引发剂）为1.0298%,w（分散剂）为0.2374%,反应温度88℃,该聚合物的吸油倍率最大值为16.0340g柴油/g树脂。