功能性水性聚氨酯的研究进展

水性聚氨酯具有绿色、环保的特点,广泛应用于涂料、胶黏剂和表面整理剂等领域,但存在着力学性能低、热稳定性差的缺点。基于此,综述了近几年用于提升水性聚氨酯力学性能和热稳定性的方法,并就水性聚氨酯的应用领域进行了介绍,旨在为科研人员开发、合成新型水性聚氨酯提供帮助。     

水性聚氨酯胶黏剂的研究进展

水性聚氨酯胶黏剂具有极性强、化学性质活泼的异氰酸酯基(-NCO)和氨酯基(-NHCOO),使其具有较好的粘结力,且以水为介质,无毒无污染。并随着全球对环境友好型材料的不断倡导,环保意识的不断深入人心,环保型的水性聚氨酯胶黏剂将不断代替溶剂型聚氨酯胶黏剂成为胶黏剂的主流,但其一些性能并不能满足人们的要求。综述了水性聚氨酯胶黏剂的丙烯酸酯改性、复合改性和有机硅改性,并对未来进行了展望。     

水性聚氨酯胶黏剂的改性研究进展

水性聚氨酯胶黏剂含有极性很强、化学活泼性很高的异氰酸酯基（-NCO）和氨酯基（-NHCOO-）,使之具有优良的化学粘接力,其不污染环境,应用领域、用途也愈来愈广泛。阐述了水性聚氨酯的制备方法、分类,并对自乳化法制备工艺中的几种方法作了一个简单的比较。通过分析环氧树脂、丙烯酸酯、有机硅改性水性聚氨酯胶黏剂的研究状况及优缺点,进而介绍了丙烯酸树脂和有机硅对水性聚氨酯的多重复合改性及其应用,提出了对水性聚氨酯胶黏剂发展的几点看法。     

车用水性聚氨酯胶黏剂及其发展

聚氨酯胶黏剂具有优良的粘接性、柔韧性、耐油性、耐冲击性、耐磨性、耐低温性等.其品种繁多,分子结构可调性强,粘接适用范围广.介绍了车用聚氨酯胶黏剂的功用特点,分析了水性聚氨酯胶黏剂的分类及合成方法,研究了车用水性聚氨酯胶黏剂的应用领域,指出了车用水性聚氨酯胶黏剂的发展前景和趋势.     

技术信息

福建物质结构研究所等单位开发水性聚氨酯胶黏剂中国科学院福建物质结构研究所及福建创鑫科技开发有限公司等单位联合开发出水性聚氨酯胶黏剂技术。研究开发出具有自主知识产权的批次吨级水性聚氨酯鞋用胶黏剂     

水性乙烯基聚氨酯胶黏剂

所谓水性乙烯基聚氨酯,常称水性乙烯基胶黏剂,按规范称水性高分子-异氰酸酯系胶黏剂,是指水溶性高分子(PVA、纤维系高分子等)、乳液(醋酸乙烯、EVA、SBR、丙烯酸酯等)、填料(CaCO3等)为主要成分的主剂与以多官能-NCO化合物为主要成分的同化剂配合,形成具有三维结构、耐水、耐热、耐沸水煮等性能得到改善的一类木材用胶黏剂。它为一非醛类胶黏剂代表。它与水性聚氨酯不同,     

水性聚氨酯胶黏剂发展概况

简述可水分散性多异氰酸酯胶黏剂、乙烯基聚氨酯水性胶黏剂和水分散性聚氨酯(PUD)胶黏剂等水性聚氨酯胶黏剂国内外应用和技术发展状况,对我国水性聚氨酯胶黏剂的发展提出初步看法和建议。     

福建物质结构研究所等单位开发水性聚氨酯胶黏剂

中国科学院福建物质结构研究所及福建创鑫科技开发有限公司等单位联合开发出水性聚氨酯胶黏剂技术。研究开发出具有自主知识产权的批次吨级水性聚氨酯鞋用胶黏剂工业化制备成套工艺技术,为年产万吨和10万吨级水性聚氨酯胶黏剂生产线建设提供了技术支撑。建立了水性聚氨酯树脂的研究方法,实现了水性聚氨酯树脂不同性能指标的控制,并可进行快速高分子试验配比的设计和分析。率先在国内研制出适用于水性聚氨酯合成的磺酸盐型亲水扩链剂,实现了原材料的国产化。另外还成功开发出用于水性聚氨酯的脱丙酮工艺技术。     

水性聚氨酯胶黏剂在中国发展现状

本文通过分析水性聚氨酯胶黏剂的科技发展与在中国的应用现状,对国内的水性聚氨酯胶黏剂产品取得很大进步进行了肯定,然后分析了水性聚氨酯胶黏剂的使用需求,与在使用中遇到的一些问题,并且提出了水性聚氨酯胶黏剂使用建议。     

聚氨酯胶黏剂

综述了聚氨酯胶黏剂的特性和种类,以及国内聚氨酯胶黏剂研究现状;概述了近年来国内外聚氨酯胶黏剂研究和应用进展,重点介绍了鞋用聚氨酯胶黏剂、汽车用聚氨酯胶黏剂、包装用聚氨酯胶黏剂、建筑用聚氨酯胶黏剂以及木材用聚氨酯胶黏剂等的研究进展,并对其进行了分析,结合实际情况对今后聚氨酯胶黏剂的发展方向做出了展望,指出聚氨酯胶黏剂在蒸煮袋复合薄膜及水性聚氨酯胶黏剂和反应热熔胶方面的实际需求。     

Effect of Long-Chain Acrylate on the Properties of Polyacrylate/Nano-SiO2 Composite Leather Finishing Agent

Polyacrylate/nano-SiO₂ composite leather finishing agent was prepared via emulsion polymerization with butyl acrylate, methyl methacrylate, lauryl methacrylate as the main raw materials. The effects of different polymerization processes, lauryl methacrylate on the properties of composite were studied. The results show pre-emulsified emulsion polymerizations obtain a lower gel rate and higher conversion rate. Adding lauryl methacrylate can improve the water resistance, physical and mechanical properties of the composite film. Leather finished with P(Butyl acrylate/Methyl methacrylate/Lauryl methacrylate)/nano-SiO₂ composite latex show lower water-vapor permeability, lower water uptake and better resistence to the external force than that of the leather finished with P(Butyl acrylate/Methyl methacrylate)/nano-SiO₂ composite latex.     

Surface and mechanical properties of an organic-inorganic super- hydrophobic coating using modified nano-SiO2 and mixing polyurethane emulsion as raw materials

A series of organic-inorganic super-hydrophobic coatings were prepared using nano-SiO₂ particles modified by fluorine and silicone coupling agents, and a mixing polyurethane emulsion as main raw materials. The mixing polyurethane emulsion was consisted of the polyurethane emulsion end-terminated by double bond (WPUD) and polyurethane emulsion modified by silicone (WPUS). The influence of content of modified nano-SiO₂ particles and the weight ratio of WPUS to WPUD on microstructure and hydrophobicity of the coating surface were studied. The morphologies of coating surface were examined using SEM and AFM, hydrophobicity of the coating was researched by examining static water contact angle and so on. It was found that modified nano-SiO₂ particle was an indispensable factor during the preparation of super-hydrophobic coating. The roughness and hydrophobicity of the coating surface were enhanced obviously with an increase of the content of the modified nano-SiO₂ particles. When the content of the modified nano-SiO₂ particles increased up to 1.5%, the surface of coating possessed good super-hydrophobicity, and static water contact angle reached 169.1°. It was also noticed that the weight ratio of WPUS to WPUD in the base layer has also an important influence on the hydrophobicity and mechanical property of coating surface. With an increase of the ratio of WPUS to WPUD the hydrophobicity of the coating was enhanced, the tensile strength and peel strength reduced, but the elongation at break increased. When the weight ratio of WPUS to WPUD reaches up to 9/100, the static water contact angle reaches the maximum value of 169.1°.     

核壳型纳米SiO2/含氟聚丙烯酸酯复合乳液的合成与表征

采用原位乳液聚合法,在可聚合阴离子乳化剂/非离子乳化剂复配体系下,以γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)改性的纳米SiO2、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)等为核相组成,以MMA、BA及甲基丙烯酸十二氟庚酯(DFMA)为壳相单体,合成纳米SiO2/含氟聚丙烯酸酯复合乳液.考察了纳...     

Preparation of nano-TiO2/polyurethane emulsions via in situ RAFT polymerization

Stable nano-TiO₂/polyurethane (PU) emulsions were prepared via in situ reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization of 2-hydroxyethyl acrylate (HEA)-capped PU macromonomer, using azobisisobutyronitrile (AIBN) as a radical initiator and 2-{[(butylsulfanyl)carbonothioyl]sulfanyl} propanoic acid (BCSPA) anchored onto TiO₂ nanoparticles (TiO₂-BCSPA) as a RAFT agent. When the molar ratio of AIBN to TiO₂-BCSPA was changed from 1:3 to 1:10, the polydispersity index (PDI) of polymers in the emulsions decreased from 1.83 to 1.06, due to more effective RAFT polymerization in the emulsions. The TiO₂ nanofillers were well-dispersed throughout the polymer films. The tensile strengths of the nanocomposite films were significantly enhanced due to coordination bonding between the TiO₂ nanofillers and the –COOH end groups of the polymers, as evidenced by the FT-IR spectral data.     

Enhancement of polystyrene composites by hyper-branched polymer-grafted nano-SiO2

Hyper-branched poly(styrene) (HPS) made from copolymerisation of styrene (St) and a branching monomer divinylbenzene (DVB) in the presence of a chain transfer agent n-dodecanethiol (C₁₂SH) was grafted onto the surface of nano-SiO₂ via emulsion polymerisation (donated as HPS-SiO₂). A series of PS/HPS-SiO₂ composites were obtained by the addition of prepared HPS-SiO₂ into the pure PS. The structures and properties of the product were characterised by Fourier-transform infrared spectra (FT-IR), differential scanning calorimetry, thermogravimetric analysis and dynamic mechanical analysis (DMA). The results showed a strong interface interaction between HPS and nano-SiO₂ indicating that the HPS has grafted onto the surface of nano-SiO₂. The storage modulus, Young’s modulus, glass transition temperature (T_g) and thermal decomposition temperature of the composite were increased apparently by loading an appropriate amount of HPS-grafted SiO_2.     

Effect of acrylic acid and hydroxyethyl methacrylate modified nano-SiO2 particles on poly(methyl methacrylate-hydroxyethyl methacrylate) soap-free emulsion polymerization

Nano-SiO₂ powder was modified with acrylic acid (AA) and hydroxyethyl methacrylate (HEMA), respectively. The kinetics of the soap-free emulsion polymerization of methyl methacrylate (MMA) and HEMA in the presence of unmodified or modified nano-SiO₂ particles was investigated. The structure of the nano-SiO₂ particles and the Poly(MMA-HEMA) composite emulsion was characterized by Fourier transform infrared spectroscope (FT-IR). The particle size and size distribution of the emulsion, the morphology of emulsion particle, the surface tension, and ionic conductivity of these systems before and after polymerization were determined. The IR spectra showed that the organic modifiers were incorporated onto the surface of the nano-particles. In addition, the solid content and monomer conversion of the Poly(MMA-HEMA) composite emulsion with modified nano-SiO₂ are higher than that with original inorganic particles. The particle size became smaller and the particle distribution narrowed after applying the modified nano-SiO₂ particles. The SEM observation demonstrated that the shapes of these emulsion particles were uniform sphere. The surface tension and ionic conductivity increased significantly after polymerization.     

纳米SiO2/聚氨酯-含氟丙烯酸酯杂化乳液的合成与表征

采用种子乳液聚合法,以聚氨酯（PU）乳液为种子（在聚合过程中为壳相）,甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）、甲基丙烯酸十二氟庚酯（DFMA）和γ-甲基丙烯酰氧丙基三甲氧基硅烷（KH-570）改性的纳米SiO₂组成的混合物为核相,合成了具有核壳结构的纳米SiO₂/聚氨酯-含氟丙烯酸酯（SiO₂/FPUA）复合乳液。考察了纳米SiO₂和DFMA用量对乳液聚合过程及乳胶膜性能的影响。通过傅里叶红外光谱（FT-IR）、接触角（CA）、透射电子显微镜（TEM）、热重（TG）、差示扫描量热仪（DSC）和力学性能测试（MPT）等表征乳液的结构形态、乳胶膜的表面性能和综合性能。结果表明：乳胶粒子呈现“反相核壳”结构,以聚丙烯酸酯（PA）相为核,PU相为壳;由于纳米SiO₂和DFMA的协同作用,涂膜的疏水性和综合性能得到了较大的提高。     

Preparation and properties of fluorinated silicon two‐component polyurethane hydrophobic coatings

A polyurethane (PU) hydrophobic coating was prepared by the two‐component method, polycarbonate diol and isophorone diisocyanate becoming a two‐phase composition. The PU films with hydrophobic surface were prepared by establishing a rough structure on the surface of silica (SiO₂) modified with silane coupling agents (γ‐(2,3‐epoxypropoxy)propytrimethoxysilane (KH560) and (heptadecafluoro‐1,1,2,2‐tetradecyl)trimethoxysilane (FAS)). First, the surface of SiO₂ was covered by a layer of hydrophobic methyl and fluorocarbon (C–F) groups. Then, the SiO₂ and modified SiO₂ were obtained by the introduction of KH560 and FAS with the silanol reaction by ultrasonic stirring. The effect of SiO₂ and modified SiO₂ on the structure and hydrophobic properties of PU was investigated by a series of test instruments. The results showed that the introduction of SiO₂ and modified SiO₂ was beneficial for increasing the roughness of the PU coating surface; the roughness of FAS/SiO₂‐PU could reach up to 14.790 nm, four times better than pure PU. A hydrophobic modified PU coating with water contact angle 123° was fabricated by using the hydrophobic C–F group FAS as a low surface energy material and establishing a micro rough structure on the surface of PU. Moreover, PU modified with KH560 and FAS can reduce the glass transition temperature (T_g) of soft segments, resulting in improvement of micro‐phase separation. © 2020 Society of Chemical Industry     

Pickering emulsion polymerization: Preparation of polystyrene/nano-SiO2 composite microspheres with core-shell structure

Polystyrene/nano-SiO₂ composite microspheres (PS/nano-SiO₂) with core-shell structure were successfully synthesized in a Pickering emulsion route using nano-SiO₂ particles as stabilizers, which were organically modified by methacryloxypropyltrimethoxysilane (MPTMS) which containing a reactive CC bond. The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transformation infrared spectrum (FTIR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). In addition, bare PS spheres could also be obtained by changing synthetic conditions. It was found that the morphology of the resulting products depends on particle concentration, particle wettability and pH value of particle dispersion. A possible mechanism for the formation of the composites with different morphologies is proposed.     

可聚合乳化剂合成含氟丙烯酸酯无皂乳液及其性能

以甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）、甲基丙烯酸六氟丁酯（HFMA）等为主要原料,采用预乳化种子乳液聚合法合成了含氟丙烯酸酯无皂乳液,考察了可聚合乳化剂烯丙氧基壬基酚聚氧乙烯（10）醚硫酸铵（DNS-86）和HFMA的用量对无皂乳液的电解质稳定性和涂膜耐水性的影响。利用傅里叶红外光谱、差示量热扫描仪及热重分析对氟丙乳液涂膜进行了表征。结果表明：与传统乳液聚合得到的乳液及相应的涂膜相比,无皂乳液的耐电解质性能和涂膜的耐水性都有一定的提高,含氟单体有效地参与了聚合,涂膜的疏水性大大增强,耐热性显著提高。