生物大分子接枝改性丙纶非织造布研究

采用低温氧气等离子体处理聚丙烯(PP)非织造布,利用交联剂将处理后的PP非织造布与生物大分子壳聚糖或胶原蛋白进行接枝反应,探讨了接枝反应条件及改性PP非织造布的性能。结果表明:在环氧交联剂的架桥作用下,等离子体处理后的PP非织造布可接枝壳聚糖或胶原蛋白,适宜的接枝反应条件为0.1 g交联剂,45℃下12 g/L壳聚糖溶液中反应8 h,或35℃下15 g/L胶原蛋白溶液中反应6 h;经氧气等离子体处理后,PP非织造布表面引入了大量的羟基和羧基,并参与接枝反应,壳聚糖的接枝效果优于胶原蛋白;接枝改性后PP非织造布的亲水性、染色性、抗菌性及伤口愈合能力均得到提高。     

壳聚糖接枝改性PLA非织造布的制备及性能研究

为拓展聚乳酸(PLA)纤维在医疗卫生领域的应用,以交联剂及壳聚糖(CTS)对PLA纤维进行接枝改性,使CTS固定于PLA非织造布之上,采用单因素实验方法,考察了CTS接枝改性PLA非织造布的工艺条件;研究了CTS接枝改性PLA非织造布的性能。结果表明:CTS接枝改性PLA非织造布的较佳工艺条件为交联剂乙二醇二缩水甘油醚0.2 g、壳聚糖质量浓度10 g/L、浸渍温度60℃、浸渍时间6 h、焙烘温度120℃、焙烘时间3 min,使用醋酸和蒸馏水进行润洗;CTS接枝改性PLA非织造布的透气性为14%,导湿性为15 mm,平均抗弯长度为16.82 cm,对大肠埃希菌的抑菌率为77.1%,对金黄葡萄球菌的抑菌率为64.5%,具有优良的透气性、导湿性、硬挺度和抗菌性。     

碱性电池隔膜用丙纶非织造布的等离子体改性

利用低温等离子体技术对碱性电池隔膜用丙纶非织造布进行表面改性处理,探讨了影响电池隔膜性能的因素,利用红外光谱、扫描电镜对材料表面性能进行了表征分析。结果表明,不同气体的等离子体对丙纶非织造布进行表面处理的最佳工作参数放电气体、放电功率、放电时间、工作压强分别为:氩气,70 W,3 min,15 Pa;氧气,120 W,3 min,30 Pa;空气,100 W,3 min,50 Pa。通过等离子体表面活化处理,在丙纶表面引入了亲水性基团,同时产生了刻蚀,丙纶非织造布的吸碱速率可提高至每10 min 8 cm左右,吸碱率提高至250%,面电阻大幅降低至8 Ω/cm2左右。     

聚酯纤维非织造布紫外光表面接枝改性研究

以PET纤维非织造布为处理对象，研究了紫外接枝过程中不同单体、引发剂、溶剂对接枝处理后的非织造布与改性苯丙胶乳粘接性能的影响。发现以AM为接枝单体，安息香为光引发剂，水和丙酮为混合剂时效果最好。并且通过正交设计实验方法，找出最佳处理条件，经这个最佳条件处理后的非织造布浸渍改性苯丙胶乳，然后固化，测得其横向拉伸强力从未处理前的47N增加到119．28N，效果显著。     

非织造布用聚丙烯纤维

本文探讨了影响非织造布聚丙烯纤维的强度、熔点、断裂伸长度及纤维抗静电性能的主要因素。合理选择聚丙烯的熔融指数、分子量、纺丝强度、纺丝速度、冷却成形、拉伸倍数、油剂配制及其浓度等，使之生产低强高伸抗静电性能好的纤维。     

介质阻挡放电等离子体对PP非织造布的改性

利用常压介质阻挡放电(DBD)设备,研究了工作气体、放电电压、处理时间、试样布置方式等对聚丙烯(PP)熔喷非织造布吸水率和处理效果均匀性的影响。结果表明:PP非织造布试样在90kV下用氩等离子体处理40s,吸水率达672%,在氩气中混入少量氧气(Ar/O2体积比为10/1),吸水率可提高至717%;试样吸水率随处理时间及放电电压的增加均提高,可以通过增大放电电压来有效地降低处理时间;随着DBD等离子体处理强度的增加,PP非织造布整体亲水性和表观均匀性均得到有效提高;试样布满放电区域有利于提高其吸水率和处理效果的均匀性。     

丙烯酸接枝改性丙纶非织造布的吸附与解吸研究

采用丙烯酸接枝改性聚丙烯非织造布(PP-g-AA)对阳离子红X-GRL染料进行吸附与解吸,探讨了PP-g-AA对染料的吸附动力学机理、解吸过程和解吸动力学机理,以及基于动态吸附的过滤分离操作,分析了PP-g-AA对染料吸附-解吸再生循环利用的可行性。结果表明:不同初始染料浓度下,PP-g-AA的吸附动力学符合Lagergren's准二级动力学模型和双指数模型;解吸液的最佳配比为表面活性剂质量分数5%,乙醇与水的体积比3∶7,解吸率随吸附量的增大呈现先增大后减小的趋势,解吸符合Lagergren's准二级动力学模型;动态吸附-解吸再生循环10次后,染料的去除率达96%以上,再生循环8次时,PP-g-AA的跨膜压力为37.1 k Pa,水通量最大达38.6 L/(m2·h)。     

血液过滤用熔喷PBT非织造布紫外辐照接枝改性研究

研究了血液过滤用熔喷PBT非织造布的紫外辐照气相接枝改性方法。通过实验选择了丙烯酸(AAc)为接枝单体 ,探讨光照时间、预辐照时间、单体温度、引发剂浓度、氮气压力对接枝率和表面润湿张力的影响 ,结果得到最佳的紫外辐照接枝条件为 :室温下 ,光距 2 0cm ,预浸 10min ,二苯甲酮 (BP) 0 .0 37mol/L ,冲入单体的氮气流量 87.5h/L ,反应时间 30min。PBT非织造布AAc紫外辐照接枝后表面润湿张力可以达到 85mN/m左右 ,且表面润湿张力随接枝率的提高而增加     

非织造布用抗菌聚丙烯纤维的制备及性能研究

选用高效、热稳定良好的有机类抗菌剂(KJ-1)与纤维级聚丙烯(PP)粉料混炼挤出,制备非织造布用抗菌PP树脂及抗菌PP纤维,研究了抗菌剂及其添加量对PP抗菌性能、力学性能及加工性能的影响,并对非织造布用抗菌PP纤维的抗菌性能和力学性能进行表征。结果表明：抗菌剂KJ-1分解温度为260℃,可满足与PP混炼挤出加工要求;添加KJ-1质量分数为0.02%时,抗菌PP树脂对大肠杆菌和金黄色葡萄球菌的抗菌率均大于99%,灰分质量分数为0.019%,230℃时其加工性能与纯PP树脂非常接近;添加KJ-1质量分数0.02%制备2.22 dtex×40 mm非织造布用抗菌PP纤维,纺丝过程中工艺参数波动较小,喷丝板使用时间为22.8 h,纤维断裂强度为1.9 cN/dtex,断裂伸长率为325.4%,对大肠杆菌和金黄色葡萄球菌的抗菌率均大于99%,抗菌长效性达250 d以上。     

聚丙烯无纺布预辐射接枝改性及胺化研究

采用丙烯酸(AA)、二乙烯三胺(DETA)依次对聚丙烯(PP)无纺布进行预辐射接枝改性及胺化处理,研究了接枝反应及胺化反应的影响因素,并用红外光谱对产物进行表征。结果表明:随着AA用量的增加,接枝率呈先增长后下降趋势;随着反应温度的升高,反应时间的延长,接枝率增加;随着接枝率的增大,胺化反应温度的升高及反应时间的增加,胺化率增加。接枝反应温度为95℃,25 mL AA与无纺布反应2 h,接枝率可达到276%;接枝率为250%的无纺布与50 mL DETA反应7 h,胺化温度205℃,胺化率可达到73%。红外光谱分析表明,经辐射接枝及胺化处理后的PP无纺布有胺基基团。     

聚丙烯无纺布接枝改性研究

采用Co射线辐射后的聚丙烯(PP)无纺布为原料,通过接枝改性制备PP接枝共聚物。研究了接枝条件对接枝率的影响。结果表明:选择丙烯酸为接枝单体,其质量分数为30%,交联剂质量分数5%,阻聚剂用量0.30 g,接枝反应温度65℃,反应时间3 h,PP无纺布的接枝改性效果显著,接枝率达84.95%。     

Grafting modification and properties of polypropylene with pentaerythritol tetra-acrylate

The α-β transition of isotactic polypropylene (PP) under stress hasn’t received much attention although it may cause deterioration of mechanical properties. PP was modified by grafting polyfunctional monomer, pentaerythritol tetra-acrylate (PETeA) carried out in a Haake mixer at 180 °C in the presence of 2,5-dimethyl-2,5-di(tert-butylperoxy) hexane peroxide (DDHP) to enhance the melt strength and suppress formation of β crystal and α-β transition. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-rays diffraction (XRD), polarized optical microscopy (POM) and melt flow index (MFI) were used to characterize the microstructure and properties of the grafted PPs. The FTIR spectra and transient torque results indicated that the acrylic polymers were grafted onto the polypropylene chains. The grafted polypropylenes gave both high crystallization and melting temperatures, and lowered the spherulite dimensions, and increased the melt strength. The grafted branching polyacrylics retarded segmental chain movement during processing and seemed to recover the depression in fatigue experiment to some extent. This work will be benefit to the extensional processing and especially provide the information on the fatigue stability of crystal structure of isotactic polypropylene during the engineering application.     

激光表面改性对聚丙烯非织造布性能的影响

采用激光技术对聚丙烯(PP)非织造布进行表面改性处理,探讨了激光功率和进布速度对PP非织造布的面密度、厚度、抗静电性、透气性、断裂强力和色泽度(K/S)的影响。结果表明:激光表面改性对PP非织造布的抗静电性、面密度和厚度影响不大;进布速度对PP非织造布的透气性、断裂强力和K/S的影响比激光功率显著,但是激光功率相比进布速度对接触角的影响更明显;随着进布速度的提高,PP非织造布的断裂强力先增加后减小,透气性、接触角和K/S呈下降趋势;随着激光功率的增大,PP非织造布的透气性先增加后趋于稳定,断裂强力和接触角显著降低,K/S增加;当激光功率为40 W,进布速度为9.0 m/min,激光表面改性处理后的PP非织造布的综合性能较好。     

Improved antimicrobial activity of polypropylene and cotton nonwoven fabrics by surface treatment and modification with chitosan

Nonwoven polypropylene and cotton fabrics were subjected to plasma pretreatment followed by flash evaporation and radiation crosslinking acrylate polymer coating, which is based on a vacuum deposition, solvent free, process that produces high quality, uniform fabrics with various thicknesses (0.05–5.0 μm). These treated fabrics were then dipped into chitosan, carboxymethyl chitosan, and carboxymethyl chitin solution. These polysaccharides form strong complexes with the modified surface. The antimicrobial activity of these treated samples was then evaluated for their antifungal and antibacterial properties. The antifungal activity for Fusarium oxysporum f. sp. lycopersici, Verticillium albo‐atrum, and Alternaria solani (A. alternata) were examined by the disc plate method. The antibacterial activities of the modified fabrics against Clavibacter michiganensis and Pseudomonas solanacearum were also examined by the viable cell counting method. The inhibition zone of the chitosan covered samples has increased by a factor of 2–3.1 over the original pretreated samples. The chitosan‐modified fabrics showed a good antibacterial activity in killing almost 10⁵ cells/mL within 18–23 h. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Study of modified polypropylene nonwoven cloth. II. Antibacterial activity of modified polypropylene nonwoven cloths

Removal of E. coli from water by modified polypropylene (PP) nonwoven cloths which were prepared through radiation‐induced grafting of 4‐vinyl pyridine (4‐VP) onto PP nonwoven cloths and followed by quaterization was carried out by filtration. The results showed that the content and structure of the pyridinium group on PP nonwoven cloths were important factors to affect their antibacterial activity. The antibacterial activity increased with the number of piled sheets of the used nonwoven cloths and decreased with increase of the viable bacterial cell concentrations in the influent and with filtration rates. The activity detection results found that modified PP nonwoven cloths possessed the ability to capture the bacterial cell alive, and no morphological changes of adhered bacterial cells were observed using SEM; thus, the surfaces of the modified PP nonwoven cloths may not be bactericidal, but bacteriostatic. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1869–1876, 2000     

Grafting of cyclodextrins onto polypropylene nonwoven fabrics for the manufacture of reactive filters. II. Characterization

A novel method for the preparation of immobilized α, β, or γ‐cyclodextrins on polypropylene nonwoven supports has been previously presented. The obtained new materials were prepared by graft‐polymerization of glycidyl methacrylate onto polypropylene after activation of the support by the electron beam technique, followed by the coupling of cyclodextrins with the epoxide groups. The structure of the resulting materials is characterized in detail using Fourier transform infrared spectroscopy, solid state nuclear magnetic resonance analysis, differential scanning calorimetry, thermogravimetric analysis, and optical microscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2166–2173, 2000     

Grafting of cyclodextrins onto polypropylene nonwoven fabrics for the manufacture of reactive filters. I. Synthesis parameters

A novel method for the preparation of immobilized α‐, β‐, and γ‐cyclodextrins (α‐, β‐, or γ‐CD) on polypropylene (PP) nonwoven fabrics is presented. These new materials were prepared by graft‐polymerization of glycidyl methacrylate (GMA) onto PP filters using the electron‐beam technique, followed by coupling of α‐, β‐, and γ‐CDs with the epoxide group. Optimization of various reaction parameters such as time, temperature, irradiation dose, monomer, and CD concentration was carried out. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2118–2125, 2000     

聚丙烯熔喷非织造材料的空气过滤效果研究

以含粉尘粒径为0.3~10.0μm的空气为尘源,测定了纤维直径为1~5μm,面密度为20.7~54.0g/m2的聚丙烯(PP)熔喷非织造材料对空气的过滤效率,研究了材料的纤维直径、面密度及电晕驻极处理对其过滤效率的影响。结果表明:随着PP非织造材料纤维直径的减小及面密度的增加,材料的过滤效率提高;纤维直径和面密度对过滤效率的影响在一定范围内具有互补性;驻极处理可有效提高PP非织造材料的过滤效率,当粉尘粒径为0.3μm时,经驻极处理后过滤效率从85.6%提高到96.2%。