丁二酸酐交联羟基超支化聚(胺-酯)的反应及其交联膜的性质

以丁二酸酐(SA)为交联剂研究了端羟基超支化聚(胺-酯)(HPAE)的交联反应和交联膜的制备。结果表明:SA与HPAE的交联反应分为两个阶段,可以采用溶液法低温涂膜及高温交联得到HPAE/SA交联膜;改变SA的用量可控制膜的交联度,HPAE/SA交联膜的拉伸强度随SA用量的增大而提高,最高可达59.60 M Pa,膜表面的水接触角小于74.3°。     

Modifications of the hydrophilicity of heterocyclic methacrylate copolymers for protein release

A series of copolymers comprising ethyl methacrylate (EM) and tetrahydrofurfuryl methacrylate (THFMA) gelled with either THFMA monomer or hydroxyethyl methacrylate (HEMA) monomer have been developed. In this paper, we examine the water uptake characteristics of the polymer systems and address the possibility of increasing the hydrophilicity of the systems by changing the ratios of the copolymers. We have investigated whether protein release from the polymers is related to the composition of the polymer systems. More protein was released from the polymers gelled with the more hydrophilic monomer (HEMA) than with THFMA. This was consistent with the calculated diffusion coefficients, which were 10 times greater for the polymers gelled with HEMA than those gelled with THFMA. Interestingly, the water uptake and protein release profiles were not dependent on the ratio of EM and THFMA in the copolymers. This is probably due to the conflicting roles of THFMA in the copolymer; it is both the more hydrophilic component as well as a cross-linking agent. In addition, it would appear that the structural and surface topography of these polymers had more significant effects on protein release than copolymer composition.     

Surface characteristics and biocompatibility of lactide-based poly(ethylene glycol) scaffolds for tissue engineering

Novel lactide-based poly(ethylene glycol) (PEG) polymer networks (GL9-PEGs) were prepared by UV copolymerization of a glycerol-lactide triacrylate (GL9-Ac) with PEG monoacrylate (PEG-Ac) to use as scaffolds in tissue engineering, and the surface properties and biocompatibility of these networks were investigated as a function of PEG molecular weight and content. Analysis by ATR-FTIR and ESCA reveled that PEG was incorporated well within the GL9-PEG polymer networks and was enriched at the surfaces. From the results of SEM, AFM, and contact angle analyses, GL9-PEG networks showed relatively rough and irregular surfaces compared to GL9 network, but the mobile PEG chains coupled at their termini were readily exposed toward the aqueous environment when contacting water such that the surfaces became smoother and more hydrophilic. This reorientation and increase in hydrophilicity were more extensive with increasing PEG molecular weight and content. As compared to GL9 network lacking PEG, protein adsorption as well as platelet and S. epidermidis adhesion to GL9-PEG networks were significantly reduced as the molecular weight and content of PEG was increased, indicating that GL9-PEG networks are more biocompatible than the GL9 network due to PEG's passivity. Based on the physical and biological characterization reported, the GL9-PEG materials would appear to be interesting candidates as matrices for tissue engineering.     

Synthesis and Hydrophilicity Analysis of bis(propane-1,2-diol) Terminated Polydimethylsiloxanes (PDMSs)

Among silicone oligomers, polydimethylsiloxane (PDMS) is widely used industrially and has the advantage of improving the properties of other compounds, such as flame-retardant polyurethane (PU). However, as there are barriers to the synthesis of PU-grafted siloxane, owing to the polarity difference between isocyanate and PDMS, numerous research efforts are being aimed at improving the hydrophilicity of PDMS. To improve the hydrophilicity and reactivity of hydroxyl PDMS, bis(propane-1,2-diol)-terminated PDMS (G-PDMS-G) with four hydroxy (-OH) groups was synthesized through ring-opening addition to replace both ends of linear α,ω-hydroxyl PDMS (HO-PDMS-OH) with glycidol, resulting in hydrophilic PDMS rather than dihydroxy PDMS. In all cases of G-PDMS-G, the contact angle and viscosity both decreased by more than 20%, confirming the improved hydrophilicity. In particular, G-PDMS-G-3, which has the largest molecular weight, demonstrated the greatest decrease in viscosity and contact angle (33%).     

Plasma Treatment for Cellulose in Tobacco Paper-Base: The Improvement of Surface Hydrophilicity and Mechanical Property

This paper reports a plasma treatment (PT) method for improving the surface hydrophilicity and mechanical properties of cellulose in reconstituted tobacco paper-base. The absorption and infiltration rates of water droplets on PT-reconstituted tobacco paper-base-15 s were significantly accelerated. Notably, the increased content of methylene and alkyl groups enabled the tobacco paper-base to absorb more useful substrates in the tobacco extract after plasma treatment. In addition, the tensile mechanical performance of reconstituted tobacco was significantly improved after plasma treatment, which indicated that the content of organic matter absorbed by the tobacco paper-base sheet was increased. Moreover, tobacco extract infiltrated on the surface of PT-reconstituted tobacco paper-base reached 37.7° within 30 s, while it reached 79.9° on the reconstituted tobacco paper-base. Finally, the mechanism by which the surface hydrophilicity and mechanical properties of the cellulose in the tobacco paper-base were improved is discussed.     

氧等离子处理人工晶状体材料的生物相容性***

背景:氧等离子处理可有效改善双组分室温硫化硅橡胶人工晶状体材料表面的亲水性能和生物相容性,但等离子体聚合形成的薄膜可能产生卷曲和破裂或因与基质是非共价键结合而产生剥离,影响材料本身的理化性能和光学性能.目的:初步评价优选氧等离子处理表面改性后双组分室温硫化硅橡胶人工晶状体材料的体外生物相容性.方法:采用氧等离子体表面改性技术修饰疏水性双组分室温硫化硅橡胶人工晶状体材料的表面,处理功率及时间分别为:20 W、50 W、100 W和30 s、1 min、3 min、10 min.应用视频光学接触角测定仪、傅里叶变换衰减全反射红外光谱和X射线光电子能谱分析材料表面亲水性和表面化学元素组成;扫描电子显微镜和原子力显微镜观察材料表面形貌.通过人晶状体上皮细胞黏附实验观察双组分室温硫化硅橡胶表面改性前后细胞的数量及形态改变.结果与结论:最佳改性条件为100 W,30 s,20 mL/min,40 Pa.此条件改善了双组分室温硫化硅橡胶人工晶状体材料表面的亲水性,对材料表面无刻蚀作用,改善了人晶体上皮细胞在双组分室温硫化硅橡胶人工晶状体材料表面的生物相容性.     

新型亲水抗菌硅橡胶口腔印模材料的制备及性能研究

目的 合成兼具亲水及抗菌性的新型硅橡胶口腔印模材料,并探讨相关性能,为其在牙科领域中的进一步应用奠定基础。方法 在前期预实验的基础上确定了新型硅橡胶的基本配方,并以6%聚醚改性硅油作为润湿剂赋予其良好的亲水性。将自行合成的碘代长链烷基季铵盐修饰的纳米抗菌SiO2无机填料,按0%、1%、2%、3%、4%及5%的比例添加至亲水硅橡胶印模材料中,以期赋予其抗菌性,并以商品化的硅橡胶产品作为对照。测量各组硅橡胶材料的力学性能、润湿性、细节再现性、尺寸稳定性及调和时间;同时通过薄膜密着法与CCK-8法检测硅橡胶材料的抗菌性与细胞毒性;扫描电镜（SEM）观察新型硅橡胶的微观形貌。结果 当抗菌填料含量超过4%时,新型硅橡胶力学性能明显下降（P<0.05）;与对照组相比,不同组别在不同时间节点接触角、细节再现性完好且线性尺寸变化率无显著变化（P>0.05）;抗菌填料的加入不会对调和时间产生影响（P>0.05）。当加入4%抗菌填料时,抗菌率可达95.26%,展现出良好的抗菌性;所有组别细胞毒性反应差异无统计学意义（P>0.05）,说明硅橡胶材料无明显细胞毒性。硅橡胶试样断面SEM...