Surface properties of polymers treated with tetrafluoromethane plasma

Polymer films of poly(ethylene terephthalate), polypropylene, and cellophane were surface treated with tetrafluoromethane plasma under different time, power, and pressure conditions. Contact angles for water and methylene iodide and surface energy were analyzed with a dynamic contact angle analyzer. The stability of the treated surfaces was investigated by washing them with water or acetone, followed by contact angle measurements. The plasma treatments decreased the surface energies to 2–20 mJ/m² and consequently enhanced the hydrophobicity and oleophobicity of the materials. The treated surfaces were only moderately affected after washing with water and acetone, indicating stable surface treatments. The chemical composition of the material surfaces was analyzed with X-ray photoelectron spectroscopy (XPS) and revealed the incorporation of about 35–60 atomic % fluorine atoms in the surfaces after the treatments. The relative chemical composition of the C ls spectra's showed the incorporation of —CHF— groups and highly nonpolar —CF₂— and —CF₃ groups in the surfaces and also —CH₂—CF₂— groups in the surface of polypropylene. The hydrophobicity and oleophobicity improved with increased content of nonpolar —CF₂—, —CF₃, and —CH₂—CF₂— groups in the surfaces. For polyester and polypropylene, all major changes in chemical composition, advancing contact angle, and surface energy are attained after plasma treatment for one minute, while longer treatment time is required for cellophane. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1591–1601, 1997     

聚酯粉末涂料的耐久性评价及其性能改进

介绍了通过佛罗里达曝晒试验评价各类聚酯粉末涂料的耐久性。采用十二氟庚烷基长链氟碳烷基的聚酯树脂粉末涂料,较大改善涂膜表面疏水性和疏油性,为改进聚酯粉末涂料耐久性作了有益的探索。     

Molecular simulations on the hydration and underwater oleophobicity of zwitterionic self-assembled monolayers

Zwitterionic materials have attracted increasing attentions in the underwater super-oleophobic applications for its strong hydration via electrostatic interactions. Herein, molecular dynamics simulations were used to investigate the hydration and underwater oleophobicity of sulfobetaine-terminated self-assembled monolayers (SB-SAMs) with different carbon spacer lengths (CSL) between oppositely charged groups of SB molecules. Simulation results show that the hydration of SB-SAMs is positively dependent on CSL; the underwater oleophobicity is strengthened and then weakened with the increase of CSL, reaching optimal performance when CSL = 3; adhesion force of oil droplet on SB-SAMs is inversely correlated with their contact angles, reaching the minimum value when CSL = 3. Moreover, the addition of NaCl can weaken the self-association of SB molecules resulted from interactions between cationic and anionic groups, which promotes hydration and enhances underwater oleophobicity of SB-SAMs. These results will benefit for the design of novel zwitterion-based materials for anti-fouling and oil–water separation applications.     

超疏水高疏油铝滤网的制备及其耐腐蚀性能

目前针对抽油烟机铝滤网的黏附油烟及腐蚀性问题等研究较少。利用Fe Cl3溶液刻蚀并沸水处理铝滤网,并采用十七氟癸基三甲氧基硅烷对其表面进行改性,制备出具有超疏水高疏油表面的铝滤网。利用扫描电子显微镜、原子力显微镜、X射线衍射仪、傅里叶变换红外光谱仪对滤网的表面形貌和成分进行了分析,用接触角测量仪对试样的润湿性能进行了测量,用电化学工作站对试样的耐腐蚀性能进行了研究。结果表明,在铝滤网表面制备出了微纳米复合结构,对去离子水、丙三醇、二甘醇、大豆油的接触角分别达151. 00°、148. 00°、143. 00°、140.75°,对去离子水、丙三醇、大豆油的滚动角分别为1°、5°、15°,处理后的铝滤网在自然环境和高温环境中具有优异的稳定性,电化学测试表明其具有更好的耐腐蚀性能,在3.5%Na Cl溶液中的缓蚀率达85.8%。     

全氟聚醚改性聚酯粉末涂料的研究

采用熔融共聚法合成全氟聚醚改性聚酯树脂,在聚酯分子链中引入数均相对分子质量约3 000的全氟聚醚侧链。用该树脂制成的粉末涂料,不仅具有超强的防腐性和耐候性,而且具有较好的疏水性、疏油性和自清洁效果,可广泛应用于各个领域。     

含氟丙烯酸酯共聚物的合成及其涂膜表面疏水、疏油性能研究

以单体甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸、含氟(甲基)丙烯酸酯为原料,通过改变氟碳链长度、氟单体含量以及添加方式等因素,合成了一系列的含氟丙烯酸酯共聚物。利用表面接触角测试仪、红外光谱仪和多功能光电子能谱仪表征了共聚物涂膜的表面疏水、疏油性能以及表面化学成分,探讨了其影响因素。结果表明,共聚物涂膜表面疏水、疏油性能与其表面化学成分密切相关;使用长氟碳链的氟单体、增加氟单体用量以及采用在反应后期一次性加入氟单体的方法均有利于提高涂膜表面的疏水、疏油性能;当全氟辛基乙基甲基丙烯酸酯的质量分数为25%时,所得涂膜表面的氟元素质量分数达到44.284%,对水、对正十六烷的接触角分别达到127°和65°。     

Scratch-Resistant Hydrophobic Coating with Supramolecular-Polymer Co-Assembly

Supramolecular assembly for superhydrophobic coatings is known for its efficiency and efficacy. However, the mechanical fragility of the coatings limits their use as coating materials. Herein, the combination of (±)-N,N'-(trans-cyclohexane-1,2-diyl)-bis(perfluorooctanamide) CF7 , a cyclohexyl diamide-based low molecular weight gelator, with acrylate polymers for the generation of semi-transparent omniphobic coatings with significantly enhanced scratch proofness is presented. CF7 has shown the ability to self-assemble in common solvents into highly entangled fibrous networks with extreme water repellency. The incorporation of covalent polymers, specifically poly(methyl methacrylate) (PMMA) and poly(trifluoroethyl methacrylate) (PTFEMA), helps to fixate the supramolecular CF7 fibers without interfering with the self-assembled structures. The resulting coatings, namely CF7/PMMA and CF7/PTFEMA , show significantly improved mechanical resistance as well as optical transparency while maintaining excellent water and oil repellency. Furthermore, the homogeneity of the coating in bulk is confirmed by depth profiling of the 3D distribution of the components using time-of-flight secondary ion mass spectrometry imaging, which turns out to be an essential technique in order to characterize such materials.