PTFE/Cu材料动态压缩特性

通过冷等静压和冷压烧结制备出六种不同密度的聚四氟乙烯(polytetrafluoroethylene,PTFE)/Cu复合材料,并采用霍普金森系统研究了密度和制备方法对PTFE/Cu动态力学性能影响。结果表明,冷压烧结试样在其烧结过程中发生纵向膨胀,导致密度降低,且试样表面生成一层金属膜;冷压烧结试样的动态压缩性能优于冷等静压试样;冷压烧结后的PTFE/Cu材料中PTFE晶体发育更好,对Cu颗粒包裹力更大,界面结合力更高,提升了冷压烧结PTFE/Cu材料的力学性能。

PTFE/Cu材料粒子流冲击带壳装药的仿真研究

采用光滑粒子-有限元耦合(SPH-FEM)方法对PTFE/Cu材料形成粒子流冲击带壳装药进行数值模拟研究;结果表明:SPH-FEM方法,可以有效模拟PTFE/Cu材料药型罩在爆轰波的作用下形成飞散的粒子流并侵彻带壳装药的过程;不同性能的PTFE/Cu粒子流冲击带壳装药会产生基本未反应、燃烧、爆炸等现象;根据改进的HELD驻点压力引起带壳炸药起爆的临界条件,计算得到面板、炸药、背板厚度分别为2 mm、4 mm、2 mm的带壳装药的起爆下阈值为20.905 mm^3/μs^2,起爆上阈值为22.585 mm^3/μs^2。

复合化学镀Ni-Cu-P/PTFE工艺的研究

研究了PTFE悬浮量、表面活性剂复配量对复合化学镀膜的镀速、结构、成分、耐腐蚀性及耐磨性的影响,结果表明,PTFE悬浮量和表面活性剂复配量的提高,镀膜的镀速、铜的百分含量和摩擦系数均有大幅度的下降,腐蚀速度略有降低,镀膜的相结构没有大的变化,试验表明,Ni Cu P/PTFE复合化学镀膜具有优良的自润滑性能。

Cu-PTFE自润滑镀层的制备工艺及沉积过程的控制步骤研究

采用电沉积的方法制备Cu-PTFE自润滑复合电镀层,研究最佳制备工艺参数及其沉积过程的控制步骤。最佳工艺条件为:CuSO4 85 g/L,H2SO4 55 g/L,PTFE 40 g/L,电流密度4.0 A/dm2,反应温度25℃,反应时间60 min。该复合电镀层具有良好的硬度和润滑性能,并且研究沉积过程中颗粒浓度对控制步骤的影响。

正交试验法优化Ni-P-Cu-PTFE复合化学镀工艺

以Q235碳钢为基体采用化学镀方法制备了Ni-P-Cu-PTFE复合镀层,以沉积速率为考察指标采用正交试验法优化了Ni-P-Cu-PTFE配方及工艺条件,并研究了镀层的形貌、硬度、耐蚀性等。结果表明,最佳的镀液配方及工艺条件为硫酸镍30.0 g/L、硫酸铜0.8 g/L、氟化氢铵14.0g/L、次亚磷酸钠30.0 g/L、十二烷基硫酸钠0.04 g/L、硫脲0.004 g/L、柠檬酸三钠12.0 g/L、聚四氟乙烯12.0 mL/L,镀液pH值为4.5,化学镀温度80℃,施镀时间2 h。在该条件下,镀层沉积速率可达178.64 g/(m2·h),镀层硬度可达207.93 HV,获得的镀层表面致密平整,孔隙率较小,具有较好的耐蚀性。

脉冲参数对Cu-Sn-PTFE镀层结构和摩擦学性能的影响

采用脉冲电沉积的方法,在焦磷酸盐电解液中制备Cu-Sn-PTFE复合镀层,研究电流密度、脉冲频率、占空比等对镀层组织结构、成分、硬度及摩擦学性能的影响。结果表明,随电流密度和脉冲占空比的减小,复合镀层表面变得细腻,硬度逐渐增加;而随着脉冲频率的增大,镀层的摩擦因数有下降的趋势;复合镀层中的氟元素含量越高,镀层硬度越低,而镀层中的PTFE颗粒在摩擦过程中使得镀层具有优异的自润滑性能。在电流密度为2.5 A/dm^2、频率3 000 Hz、占空比60%的脉冲参数组合下,复合镀层的组织均匀,PTFE含量高,摩擦学性能也最优异。

纳米Cu粉填充碳纤维/PTFE复合材料的摩擦磨损性能

考察纳米Cu粉含量、粒径对碳纤维/PTFE复合材料摩擦磨损性能的影响,采用扫描电子显微镜分析磨损面和对偶面转移膜形貌,并探讨其磨损机制。结果表明:纳米Cu粉能提高碳纤维/PTFE复合材料的耐磨性,在高载荷下,纳米Cu粉的增强效果更加明显;纳米Cu粉的粒径越小,复合材料的耐磨性越好;添加质量分数0.3%纳米Cu粉的碳纤维/PTFE复合材料耐磨性最优,1.4 m/s,200 N下实验条件下,其磨损率比未添加时降低了45%;SEM分析显示纳米Cu粉能在对偶面上形成平整致密的转移膜,具有显微增强作用。

苯甲醇在Cu-PTFE复合电极上的电化学氧化行为

采用复合电镀制备Cu-PTFE疏水性复合电极并应用于苯甲醇的电化学氧化的研究。实验中分别测定了极化曲线、循环伏安和交流阻抗等电化学特征参数。结果表明,苯甲醇在Cu-PTFE疏水性复合电极上的电氧化电流效率为41.8%,苯甲醛的产率为83.1%,其电化学过程可能受电荷传递和浓差扩散过程综合控制。

Synergistic Antibacterial Performance of a Cu/WO₃-Added PTFE Particulate Superhydrophobic Composite under Visible-Light Exposure

Addition of TiO2 to a polytetrafluoroethylene (PTFE) particle-dispersed composite contributes to the self-cleaning properties of the water-repellent composite. However, its application is limited to outdoor usage or under ultraviolet (UV) irradiation. In this study, a novel visible-light-sensitive photocatalytic and superhydrophobic material was developed by adding Cu/WO3 to a PTFE particulate composite material to overcome this deficit. A remarkable property of this novel composite material is the synergistic antibacterial performance against Escherichia coli (E. coli), Staphylo-coccus aureus, and methicillin-resistant Staphylococcus aureus compared with the addition of Cu/WO3 without PTFE particles material. During 24-h exposure in visible light at 2000 lx, the number of viable cells of the three strains on the surface of the 8wt% Cu/WO3-added PTFE particulate composite decreased from 2 – 4 × 105 colony-formation units (CFUs) to less than 10, the limit of detection. This bactericidal rate is four times higher than that of 8wt% Cu/WO3 without PTFE particles material, which is attributed to the air trapped in the rough surface of the novel material providing additional oxygen to the photocatalytic reaction. Even for exposure to visible light at 100 lx, the decrease in CFUs of E. coli on the 12wt% Cu/WO3-added PTFE particulate composite reached nearly 2.0 logs. The characterization of the Cu/WO3-added PTFE particulate composite indicated that the composite material containing 80wt% PTFE maintained a superhydrophobic or water-repellent property with a water contact angle >150。, although the Cu/WO3 in the composite material remained hydrophilic under visible light. The Cu/WO3-added PTFE particulate composite displayed photo-catalytic reactions to decompose oleic acid adsorbed on its surface and gaseous acetaldehyde under UV-A and visible-light illumination. All results demonstrate that the Cu/WO3-added PTFE particulate composite material may be used in sterilization, as a water repellent, for self-cleaning, and in the oxidative decomposition of volatile organic compounds (VOC) both indoors and outdoors.

The Synergistic Antibacterial Performance of a Cu/WO₃-Added PTFE Particulate Superhydrophobic Composite Material

The synergistic antibacterial performance against Escherichia coli (E. coli), Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) of a Cu/WO3-added PTFE (polytetrafluoroethylene) particulate composite was reported in the previous paper. The origin of the synergistic antibacterial performance investigated by evaluating the photocatalytic decomposition of the Cu/WO3-added PTFE particulate composite material is reported in the present paper. Addition of Cu/WO3, visible-light-sensitive photocatalyst, to the PTFE particle dispersed superhydrophobic composite does not deteriorate the superhydrophobic property of the composite. Furthermore the existence of the polytetrafluoroethylene (PTFE) particles dispersed in the composite enhances the antibacterial property caused by the Cu/WO3. The authors call this “The synergistic effect”. In this study, a novel synergistic property of the Cu/WO3-added PTFE particulate composite was investigated by evaluating the degradation of gaseous acetaldehyde on the composite surface using visible light (10,000 lx) and UV-A (1 mW·cm-1) illumination. The 12 wt% Cu/WO3-8 wt% binder-80 wt% PTFE composite shows the synergistic visible-light-sensitive photocatalytic property. But 12 wt% Cu/WO3-44 wt% PTFE-44 wt% binder composite no longer shows the synergistic property of visible-light-sensitive photocatalytic property. The synergetic performance of visible-light-sensitive photocatalytic property appears only when PTFE concentration is larger than the critical point over which superhydrophobic property appears in accordance with the particulate composite model derived by the one of the authors. The hydrophobic surface leads to the low surface free energy derived by the revised Fowkes’s theory, which makes it difficult for bacteria to stick to the hydrophobic surface of the composite. Even if bacteria stick to the surface, they are decomposed by the visible-light-sensitive photocatalyst. This is the reason why the synergistic antibacterial performance against bacteria appears.

纳米金属粉填充Ekonol/PTFE复合材料的摩擦磨损性能研究

评价了分别用不同体积含量的纳米镍粉和纳米铜粉填充聚苯酯/聚四氟乙烯(Ekonol/PTFE)复合材料体系的力学性能,利用M-200型磨损试验机研究了纳米Ni、纳米Cu含量对Ekonol/PTFE复合材料摩擦学性能的影响,借助扫描电子显微镜和能谱分析手段考察试样磨损表面和磨屑,并探讨其摩擦磨损机制。结果表明,纳米Ni能在一定范围内增加Ekonol/PTFE复合材料的冲击强度;纳米金属粉填入量较小时均能增加复合材料的洛氏硬度。纳米Ni与纳米Cu均能增加Ekonol/PTFE复合材料的摩擦因数并降低磨损率。其原因在于纳米金属粉在复合材料摩擦表面富集,通过金属分子间的吸引作用,增大复合材料的摩擦因数。

聚四氟乙烯纤维辐照接枝制备弱酸性离子交换剂及其对Cu^(2+)的吸附

以聚四氟乙烯纤维为基体通过6 0 Co辐射引发与丙烯酸接枝制备弱酸性阳离子交换纤维 .产物功能基含量为 3 0 6mmol g,在pH =5时该纤维达到对Cu2 + 的最大动态吸附量为 10 7 4 8mg g.使用不同浓度HCl对饱和吸附铜的接枝纤维进行洗脱 。

电沉积制备铜-锡-PTFE自润滑复合镀层工艺参数对其性能的影响

用复合电沉积法在不锈钢基体上制备铜-锡-PTFE自润滑复合镀层,并用扫描电子显微镜、能谱仪、摩擦磨损试验机等研究了十六烷基三甲基溴化胺(CTAB)及PTFE的加入量、电流密度、沉积温度等工艺参数对复合镀层组成和性能的影响。结果表明:镀层中PTFE的含量随镀液中CTAB及PTFE加入量增加而增大,当加入量分别达到0.3 g·L^(-1)和36 g·L^(-1)时PTEE的含量最大;随电流密度的增大,镀层中PTFE含量增加,超过3 A·dm^(-2)后其含量下降;适宜的沉积温度为50～55℃;复合镀层显微硬度随镀层中PTFE含量增加而降低,当镀液中PTFE质量浓度为36 g·L^(-1)时镀层摩擦因数最低,为0.09。

聚四氟乙烯基离子交换纤维及其对Pb^(2+)、Cu^(2+)吸附性能研究

以聚四氟乙烯(PTFE)纤维为基体,通过辐射引发与丙烯酸接枝制备弱酸性阳离子交换纤维,研究了不同接枝率纤维在不同pH值条件下对重金属离子Pb2+、Cu2+的吸附性能,并探讨了该材料的热稳定性.结果表明:该纤维对Pb2+、Cu2+具有良好的吸附性能,热稳定性能良好.

铜包石墨的铜层厚度对其PTFE基复合材料摩擦学性能的影响

研究了石墨与铜包石墨填料同ＰＴＦＥ 聚合物基体的结合状态以及铜层厚度对铜包石墨－ＰＴＦＥ 复合材料的布氏硬度及摩擦学性能的影响。结果表明：铜包石墨处理可以显著提高填料与ＰＴＦＥ 的界面结合强度；复合材料的布氏硬度随铜层厚度的增加而增大，并逐渐趋于稳定；铜包石墨－ＰＴＦＥ的摩擦系数随铜层厚度的增大而逐渐增大，当铜层厚度大于１．５ μｍ 时，这种变化逐渐变得缓和，而铜包石墨－ＰＴＦＥ的磨损率则随铜层厚度的增加而呈线性降低的趋势。作者认为，填料的表面增强改性是提高聚合物复合材料摩擦学性能的一种有效的方法。

铜掺杂Ni-P-PTFE涂层的微观结构、耐蚀性和力学性能

研究了铜的掺杂量对化学镀Ni-Cu-P-PTFE复合涂层的微观结构、耐蚀性和力学性能的影响。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、电化学工作站、纳米压痕仪、HSR-2M摩擦磨损试验机分别对NiCu-P-PTFE复合涂层的微观结构、耐蚀性和力学性能进行表征和测试。结果表明,铜的掺杂对Ni-P-PTFE复合涂层的成分、微观结构、耐蚀性和力学性能都具有较大的影响,随着镀液中Cu^(2+)浓度的增加,涂层中Cu含量先增加后下降,而Ni、P和PTFE含量则先下降后增加;随着涂层中掺杂Cu含量的增加,Ni-Cu-P-PTFE涂层的耐蚀性和硬度得到改善,但其摩擦性能降低。

Application and characterization of grafted polytetrafluoroethylene fiber for enhanced adsorption of Cu(Ⅱ) in aqueous solutions

An enhanced adsorption and desorption procedure of Cu(II) onto green synthesized acrylic acid grafted polytetrafluoroethylene fiber(i.e. AA-PTFE) was conducted with various chemical methods. The results show that the optimal adsorption condition is in acetic acid, sodium acetate(HAc-Na Ac) buffer solution(p H=6.80) with the initial concentration of 0.2 mg/mL. The process is very fast initially and equilibrium time is 12 h with a high Cu(II) uptake of 112.26 mg/g at 298 K. Various thermodynamic parameters indicate that the adsorption process is spontaneous and endothermic in nature. In the elution test, 2 mol/L HCl solution achieves satisfactory elution rate and shows no significant decrease after 5 adsorption-desorption cycle, which indicates that AA-PTFE can be regenerated and reused, and due to which a reasonable amount of nondegradable polymer material is avoided in industrial use. Finally, PTFE, AA-PTFE fiber, and Cu(II) loaded AA-PTFE fiber were characterized with various techniques, including IR spectroscopic technique, SEM and EDS.

基于SPH方法的低密度粒子流成型数值仿真

为研究低密度材料药型罩形成粒子流的特性,使用AUTODYN有限元软件采用光滑粒子流体力学(SPH)方法对低密度材料药型罩形成粒子流进行数值仿真研究,进行了实验验证。药型罩材料选用聚四氟乙烯(PTFE)基体中加入质量分数为38.5%,密度为8.93 g·cm^(-3)铜粉的改性聚四氟乙烯/铜(PTFE/Cu)。研究结果表明:SPH方法可以有效地模拟爆炸和粒子流的形成,且在数值模拟过程中选择炸药粒子间距和药型罩材料粒子间距均为0.03 cm较为合适;在爆轰波的作用下,PTFE/Cu材料药型罩无法形成凝聚的射流,会形成飞散的粒子流,通过X光照片可以观察到射流是非常细小的颗粒,且光学密度沿径向增加;在40μs前仿真与实验形成粒子流的形态有很高的相似性,仿真结果与实际情况吻合性较好,而在100μs后实际粒子流的运动表现出很强的不确定性,出现螺旋、偏移等现象。

PTFE粒子对Ni-Cu-P-PTFE镀层性能的影响（英文）

采用化学镀的方法,调整化学镀工艺参数,在低碳钢表面获得了PTFE含量不同的Ni-Cu-P-PTFE镀层,研究了PTFE粒子对Ni-Cu-P-PTFE镀层表面形貌、相、显微硬度、结合强度以及摩擦等性能的影响。结果表明,Ni-Cu-P-PTFE镀层的沉积速度随着PTFE浓度的增加而升高。进一步的实验结果表明,由于PTFE颗粒自身的疏松结构和软质特性,PTFE颗粒在镀层中的共沉积会引起Ni-Cu-P-PTFE镀层的显微硬度下降。同时Ni-Cu-P-PTFE镀层的结合强度会随着PTFE浓度的增加而减小。此外,PTFE的添加会使Ni-Cu-P-PTFE镀层的摩擦系数降低,这些结果与PTFE粒子在Ni-Cu-P-PTFE镀层中的含量成反比,而与镀液中PTFE粒子的浓度没有良好的对应关系。

化学复合镀梯度镀层工艺研究

研究了梯度复合镀层N i-P/N i-P-PTFE/N i-Cu-P-PTFE的形成工艺,探讨了镀液的温度、pH值、阳离子表面活性剂浓度、PTFE浓度以及镀层中的铜含量对N i-Cu-P-PTFE镀层的沉积速度、组成和耐蚀性的影响.分别用数字测微计和能量分散X射线光谱测量了涂层厚度和组成.N i-Cu-P-PTFE镀层在HC l和NaC l溶液中的抗蚀性研究表明,N i-Cu-P-PTFE镀层的耐蚀性优于N i-P-PTFE镀层和铜.