基于单宁酸制备可喷涂超疏水材料

通过正硅酸乙酯水解合成了二氧化硅纳米粒子并形成凝胶颗粒,加入单宁酸以优化其形貌,以六甲基二硅氮烷为表面改性剂,合成了具有低表面能的超疏水喷涂材料。并用动态光散射仪(DLS)与扫描电镜(SEM)对其表征。将其分散于乙醇,并对纸张、玻璃、铝箔、木板、棉质纺织物、塑料泡沫等常见表面进行喷涂,均在短时间内构成了超疏水表面,水接触角均在150.0°以上。随后,考察了所制备超疏水涂层在受外力破坏后的自修复性与耐磨性。结果显示:1 g/L的喷涂液仅需喷三层即可构建超疏水表面,得到的涂层具有良好的透明性;超疏水涂层在受外力损坏后可用有机溶剂进行快速简易的自修复;且喷涂后的玻璃片在砂纸上负重磨损距离达到1000 mm后,接触角从153.5°降至105.5°,再喷一层即可恢复到154.0°。     

SiO_2/环氧树脂纳米超疏水材料的制备及其性能研究

利用十六烷基三甲氧基硅烷为改性剂直接对SiO_2进行改性,使硅烷中的甲氧基和带亲水性羟基的SiO_2反应,破坏纳米SiO_2中的羟基,改变其亲水性,使其同时具备亲油性和疏水性,同时以环氧树脂作为复合材料的骨架,使其成为可以有固定形状且具有涂抹性和吸附性的超疏水材料。     

喷涂法制备耐磨超疏水玻璃

采用化学刻蚀法,在钠钙硅玻璃表面进行化学刻蚀.以正硅酸乙酯(TEOS)为前驱体制备纳米二氧化硅颗粒,以十六烷基三甲基溴化铵(CTAB)控制其团聚度,然后在化学刻蚀后的玻璃表面喷涂不同团聚度的纳米二氧化硅颗粒,构建多级微纳结构,进一步经全氟癸基三乙氧基硅烷(PFTS)修饰,获得超疏水玻璃表面.利用扫描电子显微镜、接触角测...     

超疏水材料综述

随时代的发展,人们对超疏水材料的研究逐渐深入.超疏水材料具有优良的超疏水性能等,在工业、实际生活中具有较广泛的应用.但如今关于超疏水材料的资料较多,查阅起来也较繁琐.为方便人们更直观地了解有关超疏水材料的制备方法和应用领域等信息,本文将对超疏水材料进行简单综述,并提出对超疏水材料的展望.     

含芴可交联聚芳醚酮的合成

以4,4′-二氟二苯甲酮、双酚芴和二烯丙基双酚A为单体,调整双酚芴和二烯丙基双酚A的摩尔比,通过亲核取代逐步加成反应合成了一系列含芴可交联的聚芳醚酮（PAEK）;用红外光谱仪、核磁共振波谱仪、差示扫描量热仪、热重分析仪对所制备的含芴可交联PAEK的结构、热交联行为、热稳定性等进行了表征。结果表明,所制备的聚合物可通过热引发交联,交联后的聚合物具有优良的耐热性能,交联后聚合物的耐溶剂性能得到提高,最高凝胶含量达到97.5 %。     

一步法构建超疏水棉织物及性能研究

采用简单易行的一步法制备超疏水棉织物,用聚苯硫醚（PPS）与纳米二氧化硅（SiO2）改变棉织物表面结构,提高粗糙程度,使用二甲基硅油（PDMS）降低棉织物表面能,棉织物多次浸泡后烘干固化。疏水整理后的棉织物与水的接触角达到161.7°,同时表现出良好的抗寒性、耐酸性、皂洗性以及自清洁性。     

全钒液流电池用磺化聚芴醚酮质子交换膜的制备及性能

质子交换膜(PEM)作为全钒液流电池(VRFB)的核心组件之一,应当解决成本高昂、合成过程复杂等问题,并具备高质子传导率、低钒离子渗透率、高机械强度和优异化学稳定性等关键性能。本文基于四甲基双酚芴单体通过缩聚反应合成了一系列聚芴醚酮化合物PFEKs,再利用溴代反应将苯甲基功能化为溴甲基,接着通过4-羟基苯磺酸钠的SN₂亲核取代制得了一系列不同离子交换容量的磺化聚芴醚酮聚合物(SPFEKs)。通过溶液浇铸法成膜并酸化,得到一系列新型低成本PEMs。该合成路线的原料来源广泛,价格低廉,不涉及危险的磺化反应,易于工业放大。所得膜都具有良好的机械性能和氧化稳定性,其中SPFEK-40膜具有较高的质子传导率及离子选择性、较低的钒离子渗透率及面电阻,综合性能优异。以SPFEK-40膜组装的VRFB在电流密度为80 mA/cm₂^{时的能量效率}(EE)为88.2%,高于以Nafion 212膜组装的VRFB的84.8%。此外,以SPFEK-40膜组装的VRFB在30次循环后放电容量仅衰减至84.3%,远高于以Nafion 212膜组装的VRFB的66.1%。     

不同晶型CaCO3表面改性及CaCO3/PDMS超疏水涂层的制备

利用硬脂酸钠(NaSt)和油酸钠(NaOL)对文石型和方解石型两种CaCO₃粉体进行表面改性,将改性的CaCO₃粉体与聚二甲基硅氧烷(PDMS)共混,喷涂得到了CaCO₃/PDMS基超疏水涂层。采用XRD、SEM、接触角测量仪对改性CaCO₃粉体及超疏水涂层进行测试,考察了不同晶型CaCO₃用量对涂层疏水性能的影响,并对超疏水涂层的自清洁性及稳定性进行了评价。结果表明,当NaSt和NaOL用量分别为反应体系CaCO₃理论生成质量的5%时,CaCO₃粉体改性效果最好,所制备的CaCO₃/PDMS涂层疏水性最佳。当CaCO₃和PDMS质量比为1.5∶1时,CaCO₃/PDMS涂层接触角>150°,具有超疏水性。玻璃板涂层表面的亚甲基蓝污染物可以完全随着液滴被冲走,没有残留,且经过500 m L流速5 m/s的水流冲击,接触角仍达140°以上。     

（急）PDMS/ZrO2/SiO2超疏水辐射制冷薄膜的制备及性能

被动日间辐射制冷（PDRC）技术由于不需要外部能源、绿色清洁无污染而受到广泛关注。该文通过将聚二甲基硅氧烷（PDMS）和二氧化锆（ZrO2）颗粒进行复合形成分散液,将其浇铸成膜后得到PDMS/ZrO2辐射制冷薄膜材料,然后通过喷涂PDMS/SiO2分散液对其进行疏水化处理制备了一种超疏水辐射制冷薄膜材料。通过优化ZrO2粒径和喷涂液中SiO2用量,薄膜表面接触角可达156.6 ° ± 2 °,滚动角为0.3 ° ± 0.1 °,呈现优异的自清洁性能。其太阳光反射率高达95.3%,红外发射率大于90%。在太阳光直射下,薄膜可实现平均9.99 ℃的降温效果。薄膜的自清洁性能使其表面不受泥土污染从而具有稳定持久的辐射降温功能。除此之外,薄膜具有优异的机械性能、耐摩擦性能以及耐酸/碱溶液和紫外光照稳定性。     

带烯键含芴聚芳醚酮增韧改性双马来酰亚胺树脂

采用无溶剂自相溶工艺,将侧链带有烯键的含芴聚芳醚酮(RPFEK)溶解于二烯丙基双酚A（DABPA）,低温下加入4,4′-二氨基二苯甲烷双马来酰亚胺(BMDM)进行熔融共聚,再用高温固化的方式制备了带烯键含芴聚芳醚酮增韧的改性双马来酰亚胺（BMDM/DABPA）复合材料。结果表明,这种复合材料是一种互穿交联网络结构,RPFEK的引入不但对复合材料的玻璃化转变温度无明显影响,而且有利于复合材料热稳定性的提高;可反应烯键的引入提高了RPFEK与BMDM树脂的相容性与界面的粘接作用;与纯BMDM/DABPA树脂相比,10 % RPFEK增韧的BMDM/DABPA树脂的冲击强度从9.0 kJ/m2提高到了15.2 kJ/m2。     

Effect of dihydroxydiphenyl ether on poly(ether ether ketone)

A series of modified poly(ether ether ketone) (PEEK) polymers were synthesized by introduction of addition ether groups from dihydroxydiphenyl ether (DHDE) into the PEEK structure. The inherent viscosity of the DHDE-modified PEEK increased with reaction time at 320 °C. DSC thermograms showed the melting points of the obtained PEEK decreased with the increase of the DHDE content in the backbone. The degradation temperature (T_d) was slightly decreased by the introduction of DHDE. The crystallinity as measured via the X-ray diffraction (XRD) increases with the introduction of DHDE into the modified PEEK. The crystalline structure was identified as an orthorhombic structure with lattice constants a = 7.72 Å, b = 5.86 Å, and c = 10.24 Å. Due to the glass transition temperature (T_g) and the melting temperature (T_m) decreasing with the increase of the DHDE content in the reaction system. the processability of the resultant PEEK could be improved through this DHDE modification.     

Rheology and properties of melt-processed poly(ether ether ketone)/multi-wall carbon nanotube composites

Poly(ether ether ketone) (PEEK)/multi-wall carbon nanotube (MWNT) composites containing up to 17 wt% filler were prepared using a twin screw extruder. Transmission electron microscopy (TEM) images reveal that the MWNTs were homogeneously dispersed in the PEEK matrix. Linear viscoelastic measurements show that both complex viscosity and moduli increase with increasing MWNT concentration. The storage modulus, G^′ exhibits a dramatic seven order increase in magnitude around 1 wt%, leading to a solid-like low-frequency behaviour at higher loadings; the effect can be attributed to network formation at a rheological percolation threshold. Rheotens measurements show that the melt strength also increases significantly on addition of nanotubes, however, the drawability decreases. An analytical Wagner model was used to calculate the apparent elongational viscosity over a wide range of elongational rates, and to reveal significant increases on addition of MWNTs, with a similar threshold behaviour. The electrical response is also dominated by percolation effects, increasing by nearly 10 orders of magnitude from 10⁻¹¹ to 10⁻¹ S/cm, on the addition of only 2 wt% MWNTs. In contrast, the thermal conductivity and tensile elastic modulus of the composites increased linearly with nanotube content, rising by 130% and 50%, at 17 wt% MWNTs, respectively.     

含稠杂环结构聚醚酮酮的合成与性能研究(I)

以吩噻（ＯＳＰ）、对苯二甲酰氯（ＴＰＣ）和二苯醚（ＤＰＥ）为单体,在无水ＡｌＣｌ３／ＣＨ２ＣｌＣＨ２Ｃｌ／ＤＭＦ催化剂／溶剂体系中,由亲电缩聚反应合成了含稠杂环结构的聚醚酮酮共聚物,并对其基本性能进行了测定。结果表明,含ＯＳＰ结构单元ＰＥＫＫ的Ｔｇ比全对苯基位ＰＥＫＫ高４２℃以上。且随ＯＳＰ结构单元含量的增加,共聚物Ｔｇ逐渐提高,而Ｔｍ、结晶度却逐渐下降,仍具有很好的耐热性和耐溶剂性。     

特种工程塑料PES、PEEK的成型加工特性

叙述了特种工程塑料的界定,详细叙述了特种工程塑料PES、PEEK的物理性能和优异耐热性,介绍了PES、PEEK在我国的应用开发研究、应用领域和一些典型的制品。着重论述了特种工程塑料PES、PEEK的加工特性和制品成型方法,对加工设备和加工工艺做了详细的论述,为PES、PEEK的成型加工提供了理论基础和经验指导。     

复合成盐剂对聚醚醚酮合成与性能的影响

采用4,4′-二氟二苯甲酮、对苯二酚为原料,以不同比例的碳酸钾和碳酸钠为复合成盐剂,二甲苯为脱水剂,二苯砜为溶剂成功制备了一系列聚醚醚酮(PEEK)树脂。通过傅里叶红外光谱和X射线衍射对PEEK树脂结构进行了表征,证明合成的样品是对苯二酚型PEEK树脂。其次,对所制样品分别进行力学性能、特性黏度、热性能测试,详细地探讨不同钾/钠比例的复合成盐剂对PEEK性能的影响。结果表明,所有样品均展示了优异的力学性能和热性能,其熔点和初始分解温度分别大于330℃和520℃,拉伸强度介于77~101 MPa。此外,当碳酸钾和碳酸钠的物质的量比为7∶3时,PEEK树脂的综合性能达到最优。     

Synthesis and characterization of poly(arylene ether ketone) (co)polymers containing sulfonate groups

Poly(arylene ether ketone)s containing sulfonate groups were synthesized by aromatic nucleophilic polycondensation of 4,4′-difluorobenzophenone (DFK), sodium 2,5-dihydroxybenzensulfonate (SHQ) and bisphenols. Only low-molecular weight oligomer was obtained when hydroquinone (HQ) was employed as comonomer, while copolymerization of DFK, SHQ, and phenolphthalein (PL) proceeded quantitatively to high-molecular weight (reduced viscosities above 0.68 dL/g) in dimethylsulfoxide at 175 °C in presence of anhydrous potassium carbonate. The sulfonated polymers were soluble in dipolar aprotic solvents, such as N,N-dimethylactamide and N-methyl-2-pyrrolidinone. Tough membranes cast from N,N-dimethylformamide solution with SHQ/DFK mole ratios ≤65:35 were obtained. Both glass transition temperatures and hydrophilicity of the copolymers increased with the content of sodium sulfonate groups. The materials are candidates as new polymeric electrolytes for proton exchange membranes.     

Processing, structure and properties of poly(ether ketone) grafted few wall carbon nanotube composite fibers

Poly(ether ketone) (PEK) was grafted onto few wall carbon nanotube (FWNT) using in-situ polymerization of 4-phenoxybenzoic acid (4-PBA) in poly(phosphoric acid) (PPA), and fibers were processed using dry-jet wet-spinning. The PEK/FWNT weight ratio was in the range of 99/1 to 80/20. The fibers have been characterized for their morphology, structure, mechanical properties, as well as electrical conductivity. The toughness (work of rupture) of the PEK fibers, as measured from the area under the stress-strain curves, was as high as 130 J/g and often exceeded the toughness of the toughest synthetic fibers such as Kevlar™ (∼45 J/g) and Zylon™ (∼50 J/g) and approached values closer to that of spider silk (∼170 J/g). PEK and PEK-g-FWNT fibers exhibit good thermal stability with degradation onset of above 500 °C under nitrogen environment, and possess high char yield (∼50% for 5 wt% FWNT containing PEK fiber). PEK-g-FWNT fibers can be processed that exhibit good dimensional stability up to 300 °C (coefficient of thermal expansion ∼−1.2 × 10⁻⁵/°C) and the axial electrical conductivity was as high as 240 S/m at 20 wt% FWNT loading.     

Spherulitic growth kinetics in miscible blends of poly(ether ether ketone) and poly(ether imide)

Growths of poly(ether ether ketone) (PEEK) spherulites from both pure melt and its miscible blends with poly(ether imide) (PEI) have been studied by polarized optical microscopy. The nucleation density of PEEK spherulites was depressed upon blending with PEI, which can be attributed to the reduction in degree of supercooling arising from equilibrium melting point depression. A modified Lauritzen-Hoffman (L-H) theory was adopted to analyze the growth kinetics. Regime III-II transition was observed with the transition temperature decreasing with increasing PEI composition. Assuming free rotations of the virtual bonds in PEEK molecule, the side surface free energy of 12.0 erg/cm² was calculated from the characteristic ratio. The fold surface free energy of 188 erg/cm² and work of chain folding of 12.3 kcal/mol were then obtained from the modified L-H analysis.     

Synthesis and characterization of polyketones containing pendant carbazoles

Condensation of 9-(4-aminobenzene)-carbazole with 4,4′-difluorobenzophenone afforded a carbazole-functionalized poly(aryl amino ketone) (PAK-Cz). Similarly, a series of poly(ether ether ketone)s (PEEK-Cz) and poly(arylene ether ketone)s (PAEK-Cz) containing pendant carbazoles were synthesized from the copolymerization of 9-(4-aminobenzene)-carbazole, 4,4′-difluorobenzophenone and 4,4′-biphenol or 4,4′-isopropylidenebiphenol, respectively. The aforementioned polymers exhibited polystyrene equivalent number average molecular weights of up to 36 kDa, and were found to be thermally stable with high decomposition (T_d) (469-569 °C) and glass transition temperatures (T_g) (155-256 °C). UV-vis absorption and fluorescence spectra revealed that these materials exhibited highly efficient (Φ_f = 0.41-0.66) yellow-green emission (λ_em = 500-514 nm) in solution.