“私人订制”伤口敷料: 载银聚己内酯纤维膜制备及其抗菌性科普实验*

本科普实验从预防伤口感染的角度出发,以硝酸银和聚己内酯为原料,使用手持式静电纺丝机制备载银聚己内酯纤维膜,使用扫描电镜对其微观形貌进行了表征,并进行了抗菌性能测试,通过理论与实践相结合的方式,展示了原位抗菌纤维膜的制备原理及抗菌效果。本科普实验的操作难度低,实验结果通俗易懂,并涉及多学科知识的交叉,激发了学生的学习热情并拓展了视野。     

聚氨酯/黑种草子伤口敷料的制备与性能表征

利用静电纺丝技术制备了负载不同浓度黑种草子提取物(NSS)的聚氨酯(PU)纳米纤维膜(PU/NSS).对该纳米纤维膜的力学性能、亲水性、溶胀性、透气性、抗氧化性、抗菌性以及细胞毒性进行了表征,探讨了其在伤口敷料领域的应用潜力.结果表明:PU/NSS纳米纤维膜的纤维直径随着NSS含量的增加而增大,且NSS的加入改善了PU纳米纤维膜的亲水性.另外,NSS中的活性成分使PU/NSS纳米纤维膜表现出优异的抗氧化性和抗菌性,可以有效避免伤口感染.细胞毒性试验结果证明PU/NSS纳米纤维膜具有良好的生物相容性.     

ABS的MAH/St多单体熔融接枝及其对PA6/ABS共混体系相形态和力学性能的影响

通过多单体熔融接枝的方法制备出了具有较高接枝率的ABS接枝物 (ABS-g-(MAH-co-St) ) ,并对其接枝机理进行了初步探讨.研究表明 ,MAH、St接枝ABS时 ,反应主要发生在ABS中聚丁二烯的双键部位.同时 ,当MAH与St的用量比约为1:1时接枝率达到最高.ABS-g-(MAH-co-St)作为尼龙 6 (PA6)/ABS共混体系相容剂起到了良好的增容效果 .实验证明 ,相容剂使用前后 ,共混物的相区尺寸由几十μm减小到1μm以下 ,且分布更加均匀;共混物的拉伸强度和冲击强度等力学性能也同时得到均衡改善.     

烯烃聚合数学模拟研究与现状

综述了近年来国内外在烯烃聚合微观形态和宏观反应器数学模拟方面取得的研究成果,指出了烯烃聚合过程数学模拟的发展方向。     

SYNTHESIS AND CHARACTERIZATION OF ORGANOMONTMORILLONITE AND POLYAMIDE 66/MONTMORILLONITE NANOCOMPOSITES

The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods priorto the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), andtermed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were calledmodified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG andWAXD. The results show that interlayer spacings of CTAB and nylon modified MMTs are larger than that of sodium MMTs.Then polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers.The nanocomposites were characterized by WAXD,TEM and Molau experiments.The results indicate that the MMTs disperse homogeneously in the PA 66 matrix.The mechanical properties of nanocomposites,such as tensile properties and flexural properties,were also measured and show a tendency to increase with increase of MMT content and reach the maximum values at 5phr MMT content.The heat distortion temperature (HDT) of the nanocomposites(7 phr) is about 32 K higher than that of pure PA 66.     

超临界氮气对聚苯乙烯微观形态的影响——喷泉效应与层状结构的形成

当流体的温度和压力处于它的临界温度和临界压力以上时,称该流体处于超临界状态,为超临界流体．超临界流体表现出许多不同于一般气体和液体的特性,如溶质在超临界流体中的溶解度可较同温常压下溶质在同种气体中的溶解度大很多,超临界流体密度与液体的密度相近,其粘度却比液体小近百倍,导热系数比常压气体大得多等．由于超临界流体具有这些不同寻常的特性,因而以超临界萃取为代表的超临界流体已有广泛的工业应用．近年来?...     

CRYSTALLIZATION AND MELTING OF NYLON 610

Differential scanning calorimetry was used to study the crystallization andmelting of nylon 610. For nylon 610 crystallized from the melt state (260℃), the overall rateof bulk crystallization can be described by a simple Avrami equation with Avrami exponentn ≈ 2, independent of crystallization temperature. With the experimentally obtainedTm0 (235℃ ～ 255℃) of nylon 610, the fold surface free energy σe was determined to be35 ～38 erg/cm2. The effects of annealing temperature and time on the melting of quenched nylon 610 were also investigated.For nylon 610 quenched at room temperature there is only one DSC endotherm peak DSC scans on annealed samples exhibited an endotherm peak at approximately 10℃ above the annealing temperature.The size and position of the endothermic peak is strongly related to annealing temperature and time.An additional third melting was observed when quenched nylon 610 was annealed at high temperature for a sufficiently long residence time.The existence of the third melting peak suggests that more than one kind of distribution of lamella thickness may occur when quenched nylon 610 is annealed.The implications of these results in terms of crystal thickening mechanism were discussed.     

聚苯基膦酸双酚A酯的合成与表征

聚苯基膦酸双酚Ａ酯的合成与表征唐旭东陈晓婷王玉忠杨科珂王波（四川联合大学化学系成都６１００６４）吴大诚（四川联合大学轻纺学院成都６１００６５）关键词聚膦酸酯,阻燃剂,熔融缩聚,热性能聚膦酸酯类化合物是一类重要的磷系阻燃剂［１～３］,与传统的非聚合型阻燃剂相比,磷系高分子阻燃剂具有阻燃好,与聚合物基材相容性好、耐迁移、耐挥发、阻燃效果持久,因而受到广泛重视．文献已报道了聚苯基膦酸双酚Ａ酯?...     

聚碳酸酯合成工艺开发的新进展

本文从工艺开发的角度,简要评介了目前聚碳酸酯两大工业生产工艺,即光气化界面缩聚工艺和熔融酯交换缩聚工艺的研究开发新动向。