纳米微孔结构乳胶粒子的制备

纳米微孔(多孔、中空)结构乳胶粒子具有吸附、携载的功能,被广泛地应用于吸附剂、非均相催化剂、各类载体等领域。本文选用亲水性较强的AA为原料聚合单体,以P(St-BA)二元共聚物乳胶作种子乳液,通过乳液聚合方法,首先制备了表面含羧基的核壳结构乳胶粒子体系P(St-BA-AA),然后采用酸碱分步处理法,在高温条件下进行酸碱处理,得到了纳米尺寸的微孔结构乳胶粒子。通过TEM观察其内部形成的微孔结构形态,并探讨了酸碱处理时间等因素对成孔的影响。     

银-铜双金属纳米粒子/聚乳酸复合纳米纤维膜的制备及其抗菌性能

为制备高效抗菌的生物可降解聚乳酸(PLA)静电纺丝纤维膜,首先利用L-抗坏血酸对银和铜的硝酸盐溶液进行化学还原,得到银-铜双金属纳米粒子(Ag-Cu NPs)。然后将Ag-Cu NPs与PLA纺丝液共混,通过静电纺丝技术制备了不同组成的Ag-Cu NPs/PLA复合纳米纤维膜,并对其形貌、结构、亲水性和抗菌性能等进行测试。结果表明：合成的Ag-Cu NPs的粒径约为32 nm,复合纳米纤维膜中Ag-Cu NPs被PLA基体包覆,且沿着纤维径向排列,纤维表面存在大量微小的孔洞;加入Ag-Cu NPs后,Ag-Cu NPs/PLA的水接触角略微降低,亲水性增加,且Ag-Cu NPs和PLA之间仅发生物理作用,未产生明显的化学作用;相比于纯PLA纳米纤维膜,Ag-Cu NPs/PLA的抗菌率明显提高,当纺丝液中Ag-Cu NPs相对于PLA质量为7%时,复合纳米纤维膜对大肠杆菌和金黄色葡萄球菌的抑菌率均达到99%。     

纤维、纱线和针织物的导湿结构模型及应用

通过建立形成差动毛细效应的附加压力差公式，提出了有孔隙的纤维、纱线和织物导湿结构模型，对于开发此类导湿、干爽纤维、纱线和织物有着实际的指导意义。     

PET基纳米结构Ag薄膜结构及导电性能

在室温条件下,采用磁控溅射法在PET纺粘非织造布上制备了50 nm厚的纳米结构Ag薄膜,用原子力显微镜(AFM)分析溅射真空室压强对纳米结构Ag薄膜结晶状态、粒径的影响;研究了溅射工艺参数与薄膜导电性能之间的关系。实验结果表明:溅射速率随着压强的增大先增大后减小;薄膜方块电阻的变化规律和溅射速率的变化规律一致;薄膜颗粒直径随着压强的增大先增大后减小,但在压强大于1.5 Pa时,薄膜颗粒直径随压强变化未呈现明显的变化规律。     

用于PET的纳米粒子添加剂

人们对于纳米粒子的构成一直存在着很多的争议和误解。一些人只是以纳米(nm)为尺度来描述他们的产品，比如：将2μm的粒子说成2000nm的粒子。其实仅用一个尺寸指标很难对纳米粒子进行准确定义。     

纳米粒子对多糖基复合膜微观结构的影响研究进展

多糖基复合膜具有均匀、透明和可降解等特点,成为生物可降解膜领域的热点研究内容。研究发现,纳米粒子与多糖溶液共混能形成复杂的成膜液,干燥成膜后,膜的原生微观结构改变,进而改善复合膜的力学、阻隔等性能。本文简述了淀粉膜、壳聚糖膜和魔芋葡甘聚糖膜三种多糖膜的微观结构及组分分子间的相互作用,并对纳米粒子与多糖共混成膜后,复合膜微观结构和理化性能的变化进行了重点阐述,以为多糖基复合膜微观结构设计与膜性能调控研究等提供参考。     

纳米纤维基单向导湿抗菌敷料的制备及其性能

针对现有湿性敷料易滋生细菌并在创伤处形成积液的问题,以力学性能优良的聚氨酯(PU)、亲水性聚丙烯腈和超吸水性的聚丙烯酸钠为基材,以聚六亚甲基胍盐酸盐(PHGC)为抗菌剂,采用静电纺丝法制备出由纤维尺寸不同的亲水外层和疏水内层组成的纳米纤维基双层敷料,探究疏水层厚度对双层敷料单向导湿效果的影响,并分析敷料结构与性能之间的关系。结果表明:当PU内层膜纺丝时间为1 h时,所制备的双层敷料可在3.9 s内由内向外单向传输液体,此时敷料的吸水率高达1 230%,透气率约为 6.7 mm/s,透湿率约为1 350 g/(m²·d),断裂强度为 6.5 MPa,断裂伸长率为45%;PU内层膜中添加0.06%的PHGC可使敷料对大肠杆菌和金黄色葡萄球菌的抑菌率达到95%以上,无细胞毒性且具备较低的细胞黏附性能。     

PPS纤维的结构与热性能

文章借助于SEM、X衍射、热分析和DMA测试研究了PPS纤维的形态、聚集态结构与热性能。研究显示PPS纤维具有光滑的表面,为半结晶聚合物,其晶型为正交晶系,结晶度56％。PPS纤维的玻璃化转变温度在106～112℃之间,熔点Tm为284℃,热降解初始温度为542℃。     

添加纳米粒子的抗菌抗静电聚丙烯纤维研制——抗菌抗静电聚丙烯纤维的制备及性能

采用自制的纳米抗菌抗静电剂做添加剂,与常规聚丙烯切片按一定比例共混造粒,熔融纺丝制得抗菌抗静电聚丙烯纤维。在扫描电镜上观察抗菌抗静电剂在制得的母粒中的分散情况,通过DSC测试比较常规切片与抗菌抗静电母粒的热学性能,通过流变试验测试共混熔体的流动性能,研究了通过熔融纺丝制得的抗菌抗静电聚丙烯纤维的力学性能、抗菌性能和抗静电性能。     

中空纳米粒子负载光催化纤维的制备及其性能

采用溶胶-凝胶法依次在TiO2表面包覆有机物和SiO2,经高温煅烧除去中间的有机物,成功制得以TiO2为核、SiO2为壳的具有核壳中空结构的新型光催化剂(SiO2@@TiO2),并将此催化剂负载到经碱减量处理的涤纶纤维上,制得了新型光催化纤维(SiO2@@TiO2/PET).采用TEM、EDS、SEM对样品进行表征,同时测试了SiO2@@TiO2对载体的保护性能和SiO2@@TiO2/PET对甲醛的催化降解性能.结果表明:核壳中空结构不仅可以有效地防止TiO2直接和有机载体接触,保护有机载体不被腐蚀,同时甲醛气体可有效地被TiO2光催化降解.     

分子内阻燃PET纤维的结构性能

 以反应性无卤阻燃剂CEPPA为第三单体,通过共聚改性制备了分子内阻燃PET树脂,并经熔融纺丝纺制阻燃PET纤维。利用元素分析和核磁共振分析了阻燃PET树脂中的磷含量,结果表明大部分CEPPA聚合到PET分子链中。对阻燃PET纤维结晶性能、染色行为、力学性能及燃烧性能也进行了研究,结果表明阻燃PET纤维的结晶度随着磷含量的增加而降低,这导致了纤维染色性能的提高。阻燃PET纤维采用分散染料在常压沸染条件下上染率可达90%以上。此外纤维具有优异的阻燃性能,极限氧指数(LOI)值约为35%,并且抗熔滴性能得到了改善.     

工业用涤纶长丝的结构与性能

 采用显微照相系统、差热分析仪、纤维拉伸强力仪、纱线拉伸强力仪、热收缩仪等对3类工业用涤纶丝的形态结构、力学性能、热收缩性能等进行测试分析。结果表明：高强型(HT)涤纶丝单纤强度和复丝强度均大于高模低缩型(HMLS)和高强低缩型(LS)涤纶丝,断裂伸长最小,模量居中;高模低收缩型、高强低收缩型涤纶丝沸水收缩率和干热收缩率均低于高强型涤纶丝;高模低收缩型、高强低收缩型涤纶丝的熔融温度没有明显差异;高模低收缩型涤纶的性能兼顾了高强和高强低收缩丝的优点。     

白色导电涤纶的开发

通过含金属盐的聚醚酯粉末与PET切片的共聚反应制得导电母粒,导电母粒与PET切片以不同的配比共混纺丝制备出导电PET纤维。研究导电母粒质量分数对纤维电阻率的影响以及导电纤维的力学性能、水洗失重率、结晶度和染色性能等,探讨纤维的结构和导电机制。结果表明:纤维中导电母粒质量分数为38%、导电粉末质量分数为9.5%时,由工业纺丝机制得的导电纤维的电阻率为1.43×105Ω.cm,且力学性能、水洗失重率、染色性能优良,具有工业化前景。     

用于PET纤维的新型无卤素母粒

介绍了与不同的研究院所合作研制新型母粒的方法,从理论概念到最终产品,叙述从理论到完成的不同步骤和工业样品评价方法。     

Characterization of virgin and recycled poly(ethylene terephthalate) (PET) fibers

In this study, we compared the properties of recycled poly(ethylene terephthalate) (PET) fibers and virgin PET fibers. All these experiments present the differences or similarities between them on surface morphology, mechanical properties, and internal fiber structure. The results show that the surface morphology of both PET fibers is similar. According to the tests on mechanical properties, it can be observed that recycled PET fibers have a higher tensile strength and greater elongation at break. The recycled fiber has a higher degree of crystallinity while with the smaller average crystallite size based on the X-ray diffraction data. In polarized attenuated total reflectance infrared technique, the virgin fibers have a better performance than the recycled ones in orientation. Fourier Transform Infrared spectrum analysis indicates that both kinds of fibers have the similar representative groups.     

湿热处理对PTT/PET自卷曲纤维卷曲性能的影响

PTT/PET自卷曲纤维拥有三维螺旋、永久性的卷曲,赋予其纱线及织物较好的卷曲弹性伸长及卷曲回复性能。湿热处理可以消除PTT/PET织物成形过程中的残余变形和内应力,发挥PTT/PET自卷曲纤维较好的卷曲伸长回复性能,使织物获得柔软的手感和良好的尺寸稳定性。通过分析湿热处理温度和时间对自卷曲纤维的外观卷曲形态、卷曲性能的影响,确定处理条件为80℃、20min时,自卷曲纤维的卷曲性能较好,并通过正交分析得出处理温度比处理时间对纤维卷曲性能的影响更为显著的结论。     

静电和熔融纺丝法对PET纤维表面结构的影响

采用扫描电子显微镜(SEM)、原子力显微镜(AFM)和差示扫描量热仪(DSC)对溶液和熔融静电纺丝法所制备的PET纤维,以及工业熔融纺PET纤维的表面形貌和热学性能进行分析比较.结果表明,因加工成纤方式不同,熔融静电纺纤维表面光滑匀整,工业熔融纺纤维表面有明显的凹凸波浪纹,而溶液静电纺纤维表面略显蜂窝状结构.由DSC分...     

Hollow PET fibers containing silver particles as antibacterial materials

Silver ions can effectively kill bacteria due to their adsorption onto the negatively charged bacterial cell wall, thus deactivating cellular enzymes, disrupting membrane permeability, and ultimately leading to cell lysis and death. In this study, silver particles incorporated into hollow polyethylene terephthalate (PET) fibers are utilized as an antibacterial composition against the bacterium, Staphylococcus aureus. Also, a silver ion–bacterium model similar to the predator–prey model is established to analyze the inhibitory effect of silver ions on S. aureus. In contact with an aqueous solution, silver ions are released from hollow PET fibers into the solution. When a silver ion in an active medium is absorbed by a bacterium, the bacterium dies and the concentration of silver ions lowers in the medium. To keep the concentration of silver ions in the medium constant, another silver ion is released from the hollow fiber, making the silver ion–bacterium model much simpler to be solved analytically. This study shows that there is an optimal concentration of silver ions at which minimal cytotoxicity and maximal antibacterial efficacy can be achieved. To support this, experimental verification is also carried out in this study.     

PTT/PET自卷曲纤维的内部结构和弹性回复性能

通过FT-IR、DSC和显微镜观察分析了PTT/PET自卷曲纤维的化学组成结构、结晶度和横截面形状。PTT/PET纤维作为一种弹性纤维,其弹性来自于PTT组分,而湿热处理后的纤维弹性则来自于其独特的卷曲结构。     

Effects of irradiation on polyethyleneterephthalate(PET) fibers impregnated with sensitizer

Polyethylene terephthalate(PET) is difficult to be irradiation cross-linked at low dose for the aromatic groups. In this paper, trimethylolpropane triacrylate (TMPTA) was incorporated in PET fibers to sensitize the cross-linking. Changes in PET fibers subjected to electron beam irradiation at dose up to 200 kGy and dose rate 12 kGy/s were investigated by gel content, scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, thermal gravimetric analysis and X-ray photoelectron spectroscopy. The gel content was 0.14% at dose of 60 kGy and it arrived at the maximum value 0.53% at 100 kGy. Irradiated fibers showed a decrease in the breaking strength and an increase in the elongation at break. The crystal form of PET fibers had not been changed and crystallinity decreased 28% with the increasing dose. The melting temperature shifted from the original 254.28 °C to 253.44 °C. The thermal stability and the amount of non-volatile residue at 800 °C increased at dose of 100 kGy. XPS analysis indicated that the number of C-C band increased to prove the occurring of cross-link. The surface of PET fibers got rougher after irradiation and the anti-dripping property had not been improved effectively for the low degree of cross-linking.