中药贴片用ESIS热熔压敏胶的制备与性能研究

以ESIS(环氧化苯乙烯-异戊二烯-苯乙烯嵌段共聚物)为基体树脂、环氧大豆油为增塑剂和高度氢化松香为增黏树脂,制备出一种ESIS型HMPSA(热熔压敏胶)。以ESIS、增塑剂和增黏树脂用量作为试验因素,HMPSA的初粘力、剥离强度和持粘力作为考核指标,采用正交试验和载药量试验法优选出制备中药贴片用ESIS型HMPSA的最佳配方。结果表明:当m(ESIS)∶m(环氧大豆油)∶m(高度氢化松香)∶m(抗氧剂1010)=100∶80∶100∶1.4时,ESIS型HMPSA的综合性能满足中药贴片的使用要求,并且其最大载药量(34%)和水蒸气透过率[1.297 g/(m2.d)]均高于同类产品(医用SIS型压敏胶和传统天然橡胶膏)。     

SIS型热熔压敏胶的粘接性能及动态流变行为研究

以SIS(苯乙烯-异戊二烯-苯乙烯三嵌段共聚物)作为基体树脂制备HMPSA(热熔压敏胶)。研究了不同类型增塑剂与SIS基体的相容性对压敏胶(PSA)性能及动态流变行为的影响,并探讨了PSA性能与动态流变行为之间的关系。结果表明:当增塑剂与SIS中PS(聚苯乙烯)相的相容性较好时,相应HMPSA在低频(1 Hz)时的储能模量较低,初粘力较好;当增塑剂与SIS中PI(聚异戊二烯)相的相容性较好时,相应HMPSA在高频(100 Hz)时的损耗模量较高,剥离强度较大。     

SDS型热熔压敏胶动态黏弹性及微相分离结构的研究

针对SDS(苯乙烯-二烯烃-苯乙烯嵌段共聚物)型HMPSA(热熔压敏胶)的相分离结构,采用DMA(动态力学分析)法及TEM(透射电镜)对SIS/SBS(苯乙烯-异戊二烯-苯乙烯嵌段共聚物/苯乙烯-丁二烯-苯乙烯嵌段共聚物)、SIS/SBS/增黏树脂和SIS/SBS/增塑剂共混物体系的流变行为进行了对比分析,并根据聚合物动态力学参数与微相分离结构的关联性,阐明了SDS型HMPSA的黏弹性机制。研究结果表明:SIS/SBS共混物存在三相分离结构,并具有较高的储能模量;增黏树脂、增塑剂通过选择性相容改变了原有热塑性弹性体的流变行为和相分离结构,前者为两相畴结构且产生了初粘力,后者仍保持三相畴结构且具有良好的柔韧性。     

丁二烯-苯乙烯共聚物改性沥青的研究进展

介绍了丁二烯-苯乙烯共聚物改性沥青的发展状况,分析了聚合物改性剂苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)、丁苯橡胶(SBR)与基质沥青的分散性、溶胀性和相容性问题,着重论述了丁二烯-苯乙烯共聚物化学改性沥青的可能性。指出SBS、SBR与沥青适当相容并达到均匀分散,是充分发挥改性效果的前提;化学改性以及复合改性技术是提高沥青性能的重要手段。     

增黏树脂与弹性体SBS的相容性以及与热熔压敏胶性能的关系

热熔压敏胶(HMPSA)是一类不含溶剂的胶粘剂,在工业应用中占据很大的比重。工业上常用的增黏树脂有松香树脂、萜烯树脂和石油树脂三种。增黏树脂与热塑性弹性体SBS(苯乙烯/丁二烯/苯乙烯嵌段共聚物)的相容性存在一定的差异性,从工业角度重点研究和比较了增黏树脂的结构差异与性能之间的关系,并对其一般规律进行了探索。研究结果表明,当增黏树脂的软化点为100～110℃时,相应的HMPSA可获得较低的熔融黏度和较高的剥离强度,其初粘力为1～2cm;当增黏树脂的软化点为100℃时,剥离强度依次为含萜烯树脂HMPSA>含松香树脂HMPSA>含石油树脂HMPSA;当W(增黏树脂)= 210%时(相对于弹性体SBS而言),含石油树脂HMPSA的综合性能劣于含松香树脂(或含萜烯树脂)的HMPSA;当W(增黏树脂)≥210%时,HMPSA的熔融黏度低于10000mPa·s,但持粘力增强(即意味着内聚力增强)。     

嵌段共聚物结构特征对HMPSA黏附性的影响

为研究嵌段共聚物的结构特征对HMPSA(热熔压敏胶)黏附性(如初粘力、剥离强度和持粘力等)的影响,以不同结构特征的SIS(苯乙烯-异戊二烯-苯乙烯嵌段共聚物)为骨架制备了相应的HMPSA。研究结果表明:SIS弹性体的Mr(相对分子质量)越低且SI(苯乙烯-异戊二烯)双嵌段比例越高,HMPSA的初粘力就越大,而持粘力也就越低,剥离强度则随SIS弹性体的Mr增加而增大;将HMPSA的流变性(储能模量、损耗模量和动态黏度等)与黏附性关联后,HMPSA的初粘力和低频区的储能模量呈负相关,剥离强度和高频区的损耗模量相关,持粘力和系统低频区的动态黏度成正比,说明嵌段共聚物的结构对HMPSA的黏附性影响显著。     

SBS对3D打印ABS复合材料性能的影响

用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性苯乙烯-丁二烯-丙烯腈共聚物(ABS),制备3D打印用ABS改性复合材料,研究了SBS的用量对ABS复合材料性能的影响。采用熔体流动速率仪表征了复合材料的熔体流动速率,万能力学试验机和悬壁梁冲击试验机测试了复合材料的力学性能。研究结果表明,随SBS用量增加,复合材料的熔体流动速率增加,5%SBS的加入能使复合材料的熔体流动速率增加42.1%;随SBS用量增加,复合材料的冲击强度增加,弯曲强度降低;SBS能提高复合材料的断裂伸长率,增加其韧性,但同时也使拉伸强度降低。     

松香改性SMA共聚物乳液的合成与应用

以苯乙烯(St)和马来酸酐(MA)为单体、过氧化苯甲酰为引发剂和丙酮为溶剂,采用自由基无规共聚法合成了St-MA共聚物(SMA);然后以改性松香作为SMA的接枝改性剂,制成的SMA-松香接枝共聚物(SMA-g-松香)乳液作为纸张施胶剂。结果表明:经SMA-g-松香施胶液处理过的纸张,其施胶度、平滑度和耐破度均比SMA施胶纸提高了33.3%、22.2%和20.7%。     

AAS/GPNs电磁屏蔽复合材料的制备及其性能

对石墨烯进行功能化改性,以丙烯腈-丙烯酸丁酯-苯乙烯共聚物(AAS)为基体,采用溶液分散法制备了AAS/功能化石墨烯(GPNs)复合材料,并研究了其性能。结果表明:GPNs与AAS基体融合性和结合力均较好;AAS/GPNs复合材料的耐候性远优于丙烯腈-丁二烯-苯乙烯共聚物/石墨烯复合材料;GPNs用量为0.5%(w)时,复合材料的拉伸强度为52.3 MPa,较纯AAS提高了36%;电磁波频率为2~18 GHz时,复合材料的电磁屏蔽效能均大于20 dB,能够满足商业产品的需求。     

管道防腐用环氧化SBS热熔胶的研制

利用有机过氧化物对SBS(苯乙烯-丁二烯-苯乙烯三嵌段共聚物)进行环氧化改性,得到ESBS(环氧化SBS);然后以此为基体树脂,辅以适宜种类及用量的增黏树脂、增塑剂和抗氧化剂等,制备出一种油气管道防腐用ESBS基热熔胶。结果表明:制备ESBS基热熔胶的最佳配方(以质量分数计)为47%ESBS、47%增黏树脂、1%抗氧剂和5%增塑剂;经环氧化改性后,ESBS基热熔胶对极性材料的粘接强度明显提高,其剥离强度和(钢/钢)剪切强度均满足使用要求。     

松香甘油酯与甲基丙烯酸-2-羟乙酯的反应研究

松香甘油酯中的共轭双键可以与甲基丙烯酸-2-羟乙酯(HEMA)发生Diels-Alder加成发应,同时松香甘油酯具有一定的酸值,其中未反应的松香可与HEMA进行酯化反应。研究了反应温度和物料配比对加成反应和酯化反应的影响,并对产物进行了红外光谱(FT-IR)分析和热重分析。实验结果表明,反应温度升高,加成反应和酯化反应的速率会加快,230℃是理想的反应温度;随着n(HEMA)∶n(松香甘油酯)比值的增加,产物的酸值和溴值下降,当n(HEMA)∶n(松香甘油酯)=3.0∶1时,溴值(65.2 g Br/100 g)和酸值(2.95 mg KOH/g)最低;FT-IR分析表明HEMA已经连接到松香甘油酯的分子上;热重分析表明加成物的初始分解温度提高了10℃,而最终分解温度下降了11.8℃。     

改性松香季戊四醇酯在热熔压敏胶中的应用研究

以松香季戊四醇酯、歧化松香季戊四醇酯和氢化松香季戊四醇酯作增粘树脂,研究了它们对热熔压敏胶（HMPSA）外观、力学性能和使用温度范围的影响。结果表明,改性松香季戊四醇树脂与热塑性弹性体SBS具有良好的相容性;对HMPSA初粘性影响大小依次为含歧化松香季戊四醇酯＞含氢化松香季戊四醇酯＞含松香季戊四醇酯;180°剥离强度大小依次为含氢化松香季戊四醇酯＞含松香季戊四醇酯＞含歧化松香季戊四醇酯;持粘性均大于48 h。含氢化松香季戊四醇酯HMPSA的使用温度范围最宽。     

松香基聚氧乙烯醚琥珀酸单酯磺酸钠的合成及性能

以丙烯酸改性松香甘油酯为原料合成丙烯酸改性松香甘油酯聚氧乙烯醚琥珀酸单酯磺酸钠(ARGEOS)阴离子表面活性剂。测定了产品的表面物理化学性能,系统研究了环氧乙烷(EO)聚合度对产品表面物理化学性能的影响。与有关松香基琥珀酸单酯磺酸钠进行比较,结果表明,所得产品是一种性能优良的表面活性剂。     

Viscoelastic and adhesive properties of polystyrene-hydrogenated (3,4-polyisoprene and 1,4-polyisoprene)-polystyrene and polymethyl methacrylate-polybutyl acrylate-polymethyl methacrylate-based HMPSA

In the current study, hot melt pressure sensitive adhesives (HMPSA) were prepared by blending polystyrene-hydrogenated (3,4-polyisoprene and 1,4-polyisoprene)-polystyrene (HYBRAR7311), polymethyl methacrylate-polybutyl acrylate-polymethyl methacrylate (LA2250), tackifier, and other additives in an internal mixer. The compatibility of LA2250, HYBRAR7311, and glycerol rosin ester was investigated on the basis of transparency, differential scanning calorimeter, and scanning electron microscope. The results indicated that glycerol rosin ester was compatible with HYBRAR7311 and LA2250, while HYBRAR7311 was only partly compatible with LA2250. Besides, styrene-ethylene-butene-styrene block copolymers grafted MALEIC ANLYDRIDE was used as compatibilizer added into HMPSA. Although it increased the compatibility and shear strength yet the tack and peel strength were sharply decreased. Simple variable method was used to study the effect of main components on the tack, peel strength, and shear strength of HMPSA. The relationship between adhesive properties and viscoelastic properties of HMPSA was studied via dynamic mechanical analysis. The investigation showed that the smaller storage modulus at low frequency (0.01–0.1?1/s), the larger the tack. Peel strength was found proportional to G′′(f₁)/G′(f₂)(f₁?=?32.03?1/s, f₂?=?0.07?1/s). Similarly, the effect of this blend on damping performance and substrate on peel strength of HMPSA was investigated which was found excellent in this case. The peel strength of polypropylene was larger when HYBRAR7311 content was more than LA2250. However, the peel strength of polycarbonate and polyethylene glycol terephthalate was larger when LA2250 content was more than HYBRAR7311. Furthermore, the mechanical properties of HYBRAR7311/LA2250 HMPSA were found to be superior to the one-polymer HMPSA.     

Study on Adhesion Properties of a Hot-Melt Pressure-Sensitive Adhesive Based on Epoxidized Styrene–Isoprene-Styrene Triblock Copolymers (ESIS) for Transdermal Drug Delivery Systems

Pressure sensitive adhesives are a critical component in transdermal drug delivery systems (TDDS). In this study, styrene-isoprene-styrene triblock copolymers (SIS) was epoxidized with peroxyformic acid generated in situ. The hot-melt pressure sensitive adhesive (HMPSA) of ESIS with hydrogenated rosin, epoxidized soybean oil, and antioxidant was prepared. The structure and properties of ESIS were characterized with infrared spectroscopy and dynamic mechanical analysis (DMA). Water content and water vapor transmission rate on ESIS membranes were determined. The adhesion properties of HMPSA of ESIS were investigated. The experimental results showed that the HMPSA of ESIS was superior to traditional HMPSA of SIS in 180°peel strength when the substrates were polar materials, such as PVC and steel.     

高沸醇木质素改性松香树脂的合成

合成高沸醇木质素改性松香树脂,测定改性树脂的软化点、酸值和DSC-TGA曲线,并与原料松香进行比较。高沸醇木质素可以与松香反应生成木质素改性松香树脂,其软化点比松香高,酸值比松香低。松香的热稳定性通过高沸醇木质素的改性得到改善。实验结果表明高沸醇木质素改性松香比木质素磺酸盐效果更好。     

改性松香水分散液的制备及其粘合性能研究

用顺丁烯二酸酐、季戊四醇、丙烯酸丁酯、桐油、丙烯酸等对松香进行改性研究,通过正交实验综合分析了影响该实验的各个因素,最后得出了各反应物的最佳用量和最佳反应条件:季戊四醇为4.76 g,丙烯酸丁酯为15g,丙烯酸为2 g,桐油为3 g,桐油先于丙烯酸丁酯加入,然后选择质量比为1∶1的十二烷基硫酸钠和OP-10作乳化剂,利用它们的协同作用得到稳定性高的改性松香水分散液,再通过热分析、红外光谱、拉伸性能、高温稳定性、快干性等测试方法,表明改性松香水分散液的性能优于市售改性松香,可以代替部分原胶(一种以聚异戊二烯为主要成分的天然高分子化合物),而不影响其粘接性能,在一定程度上降低了成本,达到了改性的目的。     

热熔压敏胶的应用现状及发展

综述了热熔压敏胶的特点及其在欧美等发达国家和我国的应用现状,对改良型热塑性弹性体热熔压敏胶、丙烯酸酯类热熔压敏胶、有机硅类热熔压敏胶和无定形聚烯烃类热熔压敏胶的发展及应用进行了介绍。建议国内企业和科研机构开发多种用途的热熔压敏胶,扩大其使用范围,同时应加快压敏胶性能标准化进程。认为环保型和多功能化是今后热熔压敏胶的发展方向。     

Preparation of γ-linolenic acid rich triacylglycerol from borage oil via a two-step lipase-catalyzed reaction

γ-Linolenic acid (GLA) rich triacylglycerol (TAG) was successfully synthesized from glyceride, instead of glycerol, and fatty acid (FA) via Lipozyme TL IM-catalyzed esterification as a novel strategy. In the first step, GLA was enriched into glyceride fraction from borage oil by Candida rugosa lipase-catalyzed hydrolysis. The glyceride was separated from the reaction mixture by molecular distillation. GLA was enriched from 20.64% in borage oil to 45.94% in the glyceride fraction under optimum conditions. In the second step, the Lipozyme TL IM-catalyzed synthesis of TAG was carried out with the glyceride, and the FA obtained by saponification of a portion of the glyceride. The optimum conditions were the temperature of 50°C, the enzyme loading of 10%, and the vacuum level of 20 mmHg, respectively. The maximum TAG content of approximately 92% was achieved after 12 h under the optimum conditions.