DBD等离子体改性芳纶表面的动态工艺研究

采用介质阻挡放电(DBD)空气等离子体,选择不同放电强度及处理时间对芳纶表面进行连续动态处理。通过扫描电镜以及光电子能谱仪对处理前后芳纶表面进行表征。结果表明,经DBD等离子体处理后的芳纶表面粗糙度有较大提高,浸润性显著提高,且纤维表面C元素质量分数下降超过5%,0元素质量分数约上升8%;芳纶表面的粗糙度、浸润性及含氧基团含量均随放电强度和处理时间的增加而提高。     

Effect of fiber surface morphology on the hydrophilicity modification of cold plasma‐treated polypropylene nonwoven fabrics

Cold oxygen plasma was employed to give hydrophilicity modification to polypropylene (PP) nonwoven fabric (NWF). It was found that, after plasma treatment, PP NWF made from fibers with smooth surfaces can only keep its hydrophilicity for a short time and then shows a quick hydrophobic recovery at room temperature. However, this hydrophilic property can last for a long time in the case of the PP NWF made from fibers with rough surfaces. To prove the contribution of the rough surface to the long‐term hydrophilicity, this PP NWF was treated in an organic solvent to smooth the fiber surface. The hydrophilic feature of this PP NWF no longer lasts for a long time after the same plasma treatment. This observation strongly supports our opinion that the fiber surface morphology of PP NWF is a critical factor for long‐term hydrophilicity improvement after plasma treatment, which gives a positive solution to overcoming the aging effect of hydrophilicity modification often found in this technique. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Tuning of polypropylene wettability by plasma and polyhedral oligomeric silsesquioxane modifications

In this work, we have exposed polypropylene (PP) to plasma treatment and then reactively coated with polyhedral oligomeric silsesquioxane-isothiocyanate (POSS-NCS) in order to modify both of its surface characteristics: chemical composition and roughness. The results of scanning electron microscopy (SEM), atomic force microscopy (AFM), and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) showed a strong relation between plasma exposure time and PP roughness, as expected. On the other hand, the POSS-coating promoted the reduction of surface roughness, but induced a substantial increase in the water contact angle (WCA), probably due to the modification of the surface chemical nature. Besides, the surface tuning method discussed here is a fast, industrial-suitable procedure which can be applied to different polymers.     

常压等离子射流表面改性超高模量聚乙烯纤维

利用常压等离子射流(APPJ)方法对超高模量聚乙烯(UHMPE)纤维进行表面改性处理。研究了处理前后UHMPE纤维的力学性能、表面形貌、化学成分、表面粘结性能的变化。结果表明,常压等离子射流处理后,UHMPE纤维的强度未发生显著变化,纤维表面粗糙度增加,表面氧元素的含量增加,表面极性基团增加,纤维与环氧树脂之间的粘结性能得到显著的改善。     

Surface modification of polypropylene in an impulse corona discharge

The impulse corona discharge was applied to modify surface of polypropylene films. The modified surface was analyzed by contact angle measurements and ESCA. The results were compared to those treated with AC corona discharge. The impulse corona treatment provided a similar contact angle and a similar [O]/[C] ratio on the polymer surface to those in AC corona treatment. On the other hand, [N]/[C] in impulse discharge was much lower than that in AC pulse discharge. The total power input in the impulse corona discharge, however, was lower than that in AC corona discharge to achieve a similar level of surface modification. It was also observed that the lower repetition frequency, the lower contact angle, and the higher [O]/[C].     

Photochemical surface modification of polypropylene for adhesion enhancement by using an excimer laser

Polypropylene (PP) surface in water was photochemically modified to render it hydrophilic using ArF excimer laser radiation. The chemical stability of PP is attributed to the C-H and C-H₃ bonds present. Thus, it is considered that H atoms are selectively pulled out from the area irradiated with ArF excimer laser light and are replaced with OH functional groups in the presence of water. In this treatment, the irradiated sample becomes hydrophilic with enhanced adhesion properties. The experimental conditions for this surface treatment were ArF laser fluence of 12.5 mJ/cm² and a shot number of 10000. The treated PP and stainless steel were bonded with epoxy adhesive and the tensile shear strength was 46 kg/cm².     

低温等离子体对PBO纤维表面的改性

采用硅烷偶联剂处理聚对苯撑苯并双噁唑(PBO)纤维,利用常压射频低温等离子体对PBO纤维进行了表面处理,通过扫描电镜、红外光谱、光学显微镜等研究了处理时间对PBO纤维表面官能团和表面形貌的影响规律,通过单丝拔出实验测定PBO纤维基复合材料的界面剪切强度。结果表明:经过常压射频低温等离子体处理后,PBO纤维的表面形成了大量的极性基团,表面产生明显的凹坑,PBO纤维与树脂的粘接性能提高50%,纤维的拉伸强度下降5%。     

Surface modification of polypropylene by nitrogen-containing plasma

Polypropylene was treated with low pressure glow discharge plasma for the introduction of functional groups in its surface using plasma of different types. For this purpose plasma containing nitrogen and hydrogen and coating by deposition of thin plasma polymerized layers of functional group carrying monomer with NH₂ on it were used. The surface elemental composition was changed stoichiometrically by adjusting the plasma conditions depending on the feeding and plasma density. The optimum power plays an important role in the control of surface reactions between surface reactive species and plasma reactive species. Plasma-Polymerized-Allylamine (PPAa) thin film prepared with r.f. continuous and pulse wave power was characterized to study surface amine functionality. The surface amine content of PPAa at r.f. pulse wave power could be retained more efficiently than that of PPAa at r.f. continuous wave power because of less fragment of monomer. The stability test of r.f. pulse wave plasma polymerization indicated that the deposits of PPAa at the high r.f. pulse wave power were more stable than those at low r.f. pulse wave power after soaking it in tetrahydrofuran (THF).     

浅谈超高分子量聚乙烯纤维的表面处理

超高分子量聚乙烯（UHMWPE）纤维是一种性能优异的高性能纤维,但由于其表面自身特点,限制了它的应用,所以通常对其表面进行处理,以提高与树脂的界面结合力。作者介绍了几种用于UHMWPE纤维表面处理的方法,如等离子处理法。     

Surface modification of polypropylene membrane by low‐temperature plasma treatment

Microporous polypropylene membranes were low temperature plasma treated with acrylic acid and allylamine. Parameters of plasma treatment were examined and optimized for the enhancement of membrane performance properties. Excess power damaged the membrane surface and excess monomer flow rate increased the reactor pressure to interfere with the glow discharge. Longer plasma treatment time resulted in even more plasma coating and micropore blocking. The contact angle with water decreased and wettabilities increased with the increase of plasma treatment time. Deposition of the plasma polymer on the membrane surface was confirmed by FTIR/ATR spectra of the treated surface. In determining the flux, the hydrophilicity of the surface played a role as important as that of the micropore size. Adequate plasma treatment could enhance both water flux and solute removal efficiency. Results from the BSA (bovine serum albumin) solution test confirmed that fouling was greatly reduced after the plasma treatment. The BSA solution flux through the plasma‐treated membranes depended on pH, whereas pH variation had no serious effects on the untreated membrane. Modification of the surface charge by the plasma treatment should exert a substantial influence on the adsorption and removal of BSA. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1555–1566, 2001     

多聚磷酸改性PBO纤维的研究

采用多聚磷酸及其乙醇溶液(体积比1:1)对聚对苯二撑苯并二噁唑(PBO)纤维进行表面处理。通过单丝拔出剪切强度的测试来表征纤维／树脂的界面粘结性能,并通过液滴形态法来表征纤维的表面润湿性能,利用扫描电镜和X射线衍射分析探讨了表面形态及结晶结构在改性前后的变化。结果表明:PBO纤维经两种溶液分别处理1 min,5 min后,纤维／树脂的界面粘结强度分别提高24％,55％,但单丝强度均下降;纤维与水的接触角由大于90°均降低至45°左右;结晶度从原丝的56.4％分别降低至52.9％,52.3％。     

低温等离子体对UHMWPE纤维的表面改性

运用自行研制的常压低温等离子体设备对超高相对分子质量聚乙烯(UHMWPE)纤维进行了表面处理,选用正交试验法通过润湿性测试优化出不同工作气氛下的工艺条件,采用强力测试、扫描电镜(SEM)和光电子能谱仪(XPS)分析了等离子体处理前后UHMWPE纤维的性能变化。结果表明,常压低温等离子体在Ar携带丙烯酸和Ar／O2的气氛下处理UHMWPE纤维,表面改性效果良好。特别是选用Ar／O2流量比100:1,处理速度为5．8 m／min,输出功率189 W,可满足连续化生产。     

氧气低温等离子体对PBO纤维的表面改性

采用氧气低温等离子体对聚对苯撑苯并双噁唑(PBO)纤维进行表面改性,讨论了处理时间、处理功率及气压对PBO纤维单丝强度、与环氧树脂基体的界面剪切强度(π_(IFSS))、形态结构、表面元素组成和亲水性的影响。结果表明:在处理时间为2.5 min,处理功率为30 W,处理气压为50 Pa的最佳工艺条件下,经氧气等离子处理后的PBO纤维与环氧树脂的π_(IFSS)比原丝提高60%,达9.38 MPa,与水的接触角也从105°下降到72°。     

Anomalous molecular orientation of isotactic polypropylene sheet containing N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide

Small amount of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide as a β-form nucleating agent is dissolved beyond 280 °C in a molten isotactic polypropylene (iPP) and appears as needle crystals around at 240 °C during cooling procedure. Further, iPP molecules crystallize on the surface of the needle crystals, in which c-axis of the β-form iPP crystals grows perpendicular to the long axis of the needle crystals. Under flow field at extrusion processing, the needle crystals orient to the flow direction prior to the crystallization of iPP. As a result, c-axis of the β-form iPP crystals orients perpendicular to the applied flow direction with a small amount of α-form iPP. Moreover, the vertical molecular orientation of the extruded sheet sample is responsible for unique mechanical anisotropy; the fracture occurs along the transversal direction.     

氩等离子体处理改性丙纶

探讨了改性丙纶经氩等离子体处理的工艺条件及处理后纤维的性能及表面形态。改性丙纶经氩等离子体处理后 ,失重率增大 ,回潮率增大 ,试样的回潮率为处理前的 14 0 %～ 40 0 % ,失重率 0 .3 5 %～0 .3 8%时回潮率最大。处理后丙纶表面产生较深的蚀点和凹槽。较佳的处理条件为时间 10min ,功率10 0W ,工作气体压力 5 0Pa。     

Surface modification of poly(ethylene terephthalate) fiber by excimer light

Changes in the surface topography and chemical structure on the surfaces of poly(ethylene terephthalate) (PET) fibers and films caused by the irradiation using an excimer laser beam and excimer lamp light were monitored. The SEM (scanning electron microscopy) observation suggests that a wavy shape was produced by irradiation with the excimer laser beam, while such a wavy shape was not observed when the excimer lamp light was used. The XPS (X-ray photoelectron spectroscopy) analysis of the fiber surface suggests that the O/C intensity ratio was reduced by irradiation using the laser beam, whereas this ratio gradually increased with irradiation with the lamp light. This difference is attributed to the difference in the number of photons in the laser beam, which was much higher than that in the lamp light, although the laser beam and lamp light had the same wavelength and energy. As for wettability to water, the contact angle was smallest for PET irradiated by the excimer lamp light. For adhesion studies, the PET fabric was first coated with an epoxy acrylate solution, irradiated with excimer light, dipped into RFL (resorcinol-formaldehyde-latex) adhesive, and the peel strength to rubber sheet was examined. When the irradiation by the excimer laser beam was compared with that with the excimer lamp light, the laser irradiation showed a good adhesion property even for rubber vulcanization carried out for a long time at high temperature.     

Enhancing adhesive joints between commercial rubber (SBS) and polyurethane by low-pressure plasma surface modification

The paper presents research on the two-stage process of low-pressure plasma surface modification of a commercial SBS rubber, improving its adhesion to both the polyurethane adhesive in an organic solvent (PU) and the aqueous polyurethane adhesive dispersion (ADPU). The plasma surface modification process was carried out in a flow reactor with parallel plate electrodes, in which plasma was generated by an RF glow discharge (13.56 MHz). In the first stage of the process, the Ar or O₂ plasma was used, and then, as the second stage of the modification process, the treatment was performed in H₂O plasma. The adhesive properties of the plasma-modified SBS rubber surface were determined using the 180^o-peel strength test (PS). These results were correlated with surface properties investigated using contact angle (CA) measurements, FTIR-ATR spectroscopy, XPS spectroscopy and scanning electron microscopy (SEM). The observed improvement in wettability of the plasma modified surface was attributed to the formation of hydroxyl groups, which was confirmed by spectroscopic methods (FTiR-ATR and XPS). The results of the 180^o-peel strength test showed, in turn, a clear relationship between the capacity of adhesive bonding and the amount of oxygen groups (mainly the hydroxyl groups) as well as the surface roughness, determined by SEM microscopy. It was also found that the effects of the plasma surface modification of the SBS rubber were stable for at least 72 h. The results of this work prove that cleaning and etching of the commercial SBS rubber surface in the first stage of its plasma treatment, followed by chemical modification in the second stage, lead to very strong adhesive joints.     

The effect of atmospheric plasma treatment of recycled carbon fiber at different plasma powers on recycled carbon fiber and its polypropylene composites

To increase the mechanical properties of recycled carbon fiber-reinforced polypropylene (PP) composites, recycled carbon fibers (RCF) were subjected to atmospheric plasma treatment at different plasma powers (100, 200, and 300 W). The changes on surface topography and roughness of RCF were examined by atomic force microscopy. Plasma treatment of RCF increased the roughness value of RCF. The variation of surface elemental compositions and tensile strength of RCF were determined by using X-ray photoelectron spectroscopy and tensile test, respectively. Plasma-treated RCF-reinforced PP composites were fabricated using high speed thermo-kinetic mixer. Plasma treatment of RCF at 100 W increased the tensile and flexural strength values of RCF-reinforced PP composites considerably by 17 and 11%, respectively. However, plasma treatment of RCF at higher plasma powers (200 W and 300 W) decreased tensile and flexural strength values of composites because of the etching of RCF. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47131.     

PEG-ZnO-PP复合抗静电剂及其对聚丙烯纤维的改性

选用相对分子质量分别为10 000和20 000的聚乙二醇(PEG 10000,PEG 20000)与氧化锌(ZnO)、马来酸酐(MAH)混合,再与聚丙烯(PP)共混,制备复合抗静电剂(PEG-ZnO-PP),然后将其与PP共混纺丝,制得共混纤维。研究了PEG-ZnO-PP复合抗静电剂的流动性和热性能,考察了共混纤维的力学性能和抗静电性。结果表明:复合抗静电剂的流动性和热性能因PEG的相对分子质量不同而有所不同,含PEG 10000的复合抗静电剂的流动性能较好,且其熔融热焓、熔融结晶温度、结晶放热高于含PEG 20000的复合抗静电剂。共混纤维力学性能和静电半衰期随复合抗静电剂含量的增加而减小,含PEG 20000的共混纤维抗静电效果更好。     

Surface modification of natural leather using diffuse ambient air plasma

The aim of this work was to activate the surface of dyed natural leather using a diffuse ambient air plasma treatment. The plasma was generated by the so-called diffuse coplanar surface barrier discharge (DCSBD). It was observed that a 10 s plasma treatment time is enough to decrease the water contact angle from 85° to 45°. Improvement of wettability is important for gluing of dyed leather and better adhesion of glue to leather parts. XPS study indicated that the percentage of oxygen-containing bonds responsible for hydrophilicity is significantly increased by the plasma treatment. Influence of the plasma treatment on mechanical properties of dyed leather was evaluated using tensile strength measurement and no significant changes in the surface morphology and mechanical properties were observed. The results indicate that the DCSBD technique can provide high throughput, technical simplicity and economy required by the leather industry.