有机硅改性含氟(甲基)丙烯酸酯聚合物乳液的制备及其性能研究

先合成了聚硅氧烷阴离子乳液以及链中含硅烷偶联剂和含氟单体的(甲基)丙烯酸酯聚合物乳液,并且利用羟基缩合反应,将2种乳液混合反应,通过乳液接枝共聚的方法合成了一种高硅含量的有机硅改性氟代(甲基)丙烯酸酯聚合物乳液,并采用了红外光谱对聚合物乳液分子进行了表征。测试结果表明:有机硅质量分数为20%、有机氟质量分数为12%的聚合物乳液涂膜综合性能最佳,较不含有机硅氟的聚合物乳液涂膜,其水表面接触角由77.5°增加到96°,24 h吸水率由5.3%下降到2.3%,耐水性大大增加;玻璃化转变温度由8.53℃下降到-2.74℃,聚合物分子链的柔顺性有所提高;同时乳液涂膜的初始分解温度提高了77～92℃,热稳定性也明显提高,说明此方法合成的高硅含量硅丙乳液可作为一类具有优良疏水性及低表面能的功能材料得以应用。     

长链聚硅氧烷接枝（甲基）丙烯酸酯聚合物乳液的制备及其性能

该文首先合成了聚硅氧烷阴离子乳液和链中含硅烷偶联剂的（甲基）丙烯酸酯聚合物乳液两种不同的乳液,然后通过乳液接枝共聚的方法,利用硅烷偶联剂水解基团与聚硅氧烷正离子之间的反应合成了一种高硅含量的硅丙聚合物乳液。测试结果表明,有机硅质量分数为20％的聚合物乳液涂膜性能最佳,与不含有机硅的聚合物乳液涂膜相比,其水表面接触角由 77.5。增加到95。,24小时吸水率由4.9％下降到2.3％,耐水性大大增加,同时玻璃化转变温度由8.53℃下降到-1.36℃,聚合物分子链的柔顺性有所提高,说明此方法合成的高硅含量硅丙乳液涂膜可作为一类具有优良耐水性及良好的表面疏水性的功能材料得以应用。     

聚硅氧烷-(甲基)丙烯酸酯共聚乳液的制备与性能

八甲基环四硅氧烷（D4）在复合乳化剂的作用下开环形成端羟基线性聚硅氧烷乳液,然后加入γ-甲基丙烯酰氧丙基三甲氧基硅（KH570）,pH=4的条件下KH570水解,再与端羟基线性聚硅氧烷脱水形成含反应双键的长侧链聚硅氧烷,再加入(甲基)丙烯酸酯单体,自由基聚合得到聚硅氧烷-（甲基）丙烯酸酯乳液。通过这种方法,有机硅单体可占到整个单体总量的80%。然后,通过29Si NMR 、FT-IR对含反应双键的聚硅氧烷及聚硅氧烷-（甲基）丙烯酸酯聚合物进行结构表征,并对乳液及其聚合物膜的性能进行了表征,结果表明KH570完全水解后与端羟基聚硅氧烷形成含反应双键的长侧链聚硅氧烷,同时也表明当有机硅用量为80%时乳液涂膜吸水率在最终为5.3%,表面自由能为6.56 mN/m,聚硅氧烷-（甲基）丙烯酸酯共聚聚合物最大热失重速率温度为577℃。聚合物的耐水性和热稳定性能有了很大的提高,因此,可以作为一种具有高疏水性和高耐热性的材料加以应用。     

超疏水防紫外双功能水性织物涂层的制备及性能研究

利用乳液缩聚法制备芯材为氟硅烷（ FAS13）壁材接枝紫外吸收剂的二氧化硅微胶囊,将其与有机硅树脂乳液共混,涂覆于棉织物表面形成超疏水防紫外织物涂层。通过扫描电镜和透射电镜观察微胶囊的形态和粒径,并对涂层的水接触角和防紫外性能进行了测试,同时测试了涂层的耐老化、耐磨损、耐高温以及耐酸碱性。结果表明：织物涂层中微胶囊最佳含量为 45%（其中内含 6%紫外吸收剂）,由此制备的涂层表面水接触角可达到 150°以上,并且具有较好的耐老化、耐高温、耐酸碱腐蚀、耐磨损等性能;同时该织物涂层具有优异的防紫外性,紫外线防护系数（UPF）可以达到 111.2。     

室温固化含硅甲基丙烯酸酯涂料的性能研究

制备了易溶于溶剂汽油的含硅甲基丙烯酸酯改性的丙烯酸酯共聚物，通过水接触角、吸水率、铅笔硬度以及FT-IR光谱和DSC等测试，研究了丙烯酸酯单体侧链烷基对共聚物溶解性能的影响及含硅丙烯酸酯单体及其共聚工艺对共聚物表面憎水性能和强度的影响。结果表明，采用延时后滴加含硅丙烯酸酯单体和使用催化交联剂及添加羟基硅油共混可使甲基丙烯酸异丁酯和甲基丙烯酸异冰片酯的共聚物膜表面的憎水性能和强度大大提高。     

耐污涂料用氟改性纯丙交联乳液的制备及其性能

引入含氟和交联单体,制备耐污涂料用氟改性丙烯酸酯交联乳液,考察氟单体、交联单体种类及含量对乳胶膜和漆膜接触角和耐污性能的影响。FTIR分析表明甲基丙烯酸全氟庚酯（DFMA）单体成功接枝到聚合物主链上。粒径分析表明制得的氟改性纯丙乳液粒径为90nm时,涂膜耐污性能最优。当引入6.0%DFMA,乳胶膜和漆膜与水、油的接触角都显著增大。当引入交联体系为双丙酮丙烯酰胺和已二酰肼（DAAM/ADH）,且用量为4.0%时,涂膜的综合耐污性达到11.9%。     

羟基硅油改性磺酸型水性聚氨酯的合成及性能

以磺酸型聚酯二元醇(BY3301)、甲苯二异氰酸酯(TDI)为主要原料,羟基硅油为改性剂,三羟甲基丙烷(TMP)为交联剂,合成了羟基硅油改性磺酸型水性聚氨酯。采用FTIR、TG、数显黏度计、纳米粒度仪表征了聚合物的结构与性能,探讨了羟基硅油含量对乳液及胶膜性能的影响。结果表明:随着羟基硅油含量增加,乳液粒径增大,黏度降低;胶膜表面水接触角增大,吸水率先减小后增大;胶膜拉伸强度增强,断裂伸长率先增大后减小。当羟基硅油占预聚体质量的3%时,聚合物性能最佳,其乳液粒径为85.1 nm,黏度为114.5 mPa·s,胶膜水接触角为91.7?,拉伸强度为14.78 MPa,断裂伸长率为427%,24 h吸水率仅为5.61%,由TG曲线可知,胶膜质量损失5%时,对应温度为269.9℃,较之改性前提高17.3℃。     

紫外光固化聚二甲基硅氧烷-聚氨酯涂料的合成与性能研究

选用端羟丙基聚二甲基硅氧烷（HPPDMS）、异弗尔酮二异氰酸酯（IPDI）、三羟甲基丙烷（TMP）、季戊四醇三丙烯酸酯（PETA）自制光固化有机硅聚氨酯单体;用1,6-二溴己烷和3,5-二羟基苯甲酸自制超支化（HBP）交联剂,通过FT IR、¹H NMR、Zeta电位纳米粒度分析仪对产物的结构进行分析;通过热重分析仪、拉伸测试、水接触角测试、吸水率测试等分别评价涂层的耐热性、力学性能、耐老化性、疏水性、吸水率。结果表明,自制超支化土交联剂（HBP）的引入,提高了涂层的耐热性和拉伸性能,降低了涂层的吸水率,当HBP质量分数为0.5%时,涂层的综合性能最佳,此时热分解初始温度从250℃提高到285℃,t=472.1℃时,涂层残余质量分数为50%,吸水率（24 h）从2.35%降至1.15%,水接触角为77.2°,拉伸应力12.6 MPa,拉伸应变40%。     

高性能水性UV固化聚氨酯的合成与性能研究

用环氧丙烯酸酯(EA)、羟基硅油合成了环氧/有机硅改性水性光固化聚氨酯乳液(WPU);研究了EA、羟基硅油、亲水扩链剂二羟甲基丁酸(DMBA)的用量,中和度和硅烷偶联剂的添加量对乳液和涂膜性能的影响。用红外光谱和接触角测量仪对树脂进行表征。结果表明:通过EA、羟基硅油改性的水性光固化聚氨酯涂膜的硬度高、附着力强、耐水性较好,克服了未改性水性光固化聚氨酯的缺点。当EA用量为4%、羟基硅油为2%、DMBA为8%、中和度为80%、硅烷偶联剂的添加量为1%时,水性光固化聚氨酯乳液的综合性能较好,树脂接触角大大提高。     

有机硅改性聚丙烯酸酯的表面自由能和耐水性的研究

采用种子乳液聚合法制备了有机硅－丙烯酸酯接枝共聚物乳液。通过测量水和乙二醇和硅丙接枝共聚物表面上的接触角，计算该共聚物的表面自由能，并讨论了共聚物组成对其表面自由能和吸水性的影响。试验结果表明，共聚物的表面自由能和吸水率随聚硅氧烷含量增加而下降。     

The influence of monomer types on the colloidal stability in the miniemulsion copolymerization involving alkoxysilane monomer

Unlike conventional emulsion polymerization, monomer droplet nucleation becomes dominant in miniemulsion polymerization, offering the miniemulsion polymerization a great advantage over conventional emulsion polymerization when incorporating alkoxysilane monomer, which can easily undergo premature hydrolysis and condensation reactions, into polymer latex. The extensive premature hydrolysis and condensation can lead to the issue of the colloidal instability. In this article, the influence of monomer types on the colloidal stability in the miniemulsion co-(or ter-)polymerization was investigated when incorporating alkoxysilane monomer into styrene or acrylate latex. In the cases of butyl acrylate (BA)/γ-methacryoxypropytrimethoxysilane (MPMS), BA/methyl methyacrlate (MMA)/MPMS, and BA/styrene (St)/MPMS miniemulsion polymerization, nearly no coagulum was observed. The obtained latex had a long shelf life. However, the coagulum was formed in the late stage of MMA/MPMS and St/MPMS miniemulsion copolymerization. The shelf life of the corresponding latex was short. The selection of the main monomer, which can fast consume alkoxysilane comonomer, was critical to obtain the stable latex. In this way, the alkoxysilane groups were completely buried in particles thus the coagulation caused by condensation reactions derived from the alkoxysilane hydrolysis among particles was suppressed.     

Novel crosslinking system with hydroxyl-containing polymer, alicyclic polyepoxide and polyalkoxysilane

The crosslinking system based on the reaction among alicyclic epoxide group, hydroxyl group and alkoxysilyl group in the presence of aluminum β-diketone chelate have been developed. Five kinds of reaction are possible, and the result of gas chromatography and infrared analyses indicated that the main reaction is the ring-opening reaction of alicyclic epoxide group with hydroxyl group and/or hydroxysilyl group. The acrylic resin obtained by free radical polymerization of these three kinds of functional monomers and non-functional monomers showed good curing property, and the film was superior in acid rain resistance and outdoor durability. The resin is suitable to use in automotive 2coat–1bake clear coat. The viscosity of this binder system was remarkably reduced by addition of a low molecular weight alicyclic polyepoxide compound and an alkoxysilane oligomer without affecting to its good curing property. Such a system made it possible to design novel high solid coatings. It was found that the crosslinking could be extended to the combination of a polyester polyol, an alicyclic epoxide compound and an alkoxysilane oligomer. In this case, it was necessary that the polyester polyol contained highly reactive terminal hydroxyl group in the branch chains.     

Preparation of a novel polymer monolith with high loading capacity by grafting block poly(PEGA–mPEGA) for high-efficiency solid phase synthesis

The polymer monolith for solid-phase synthesis with high efficiency was prepared through in situ copolymerization of chloromethylstyrene and ethylene glycol dimethacrylate (PCMS–EDMA). The obtained monolith was grafted by two kinds of poly(ethylene glycol) acrylate oligomer, poly(ethylene glycol) acrylate (PEGA) and poly(ethylene glycol) methyl ether acrylate (mPEGA). The monolith was grafted via activators generated by electron transfer atom transfer radical polymerization (AGET ATRP) with the increased number of functional groups (–OH). About 0.61–0.81 mmol/g hydroxyl group resulted from side groups in each grafting polymer chain. PmPEGA in the grafting block copolymer chains can increase the distance between the adjacent reactive sites of PEGA (–OH) in each polymer chain. Therefore, the grafted monoliths with the block copolymer of PEGA-co-mPEGA can give high yield (85%) and purity (93%) of the crude peptide (a difficult sequence-acyl carrier protein fragment 65–74) under the condition of high loading capacity (0.76 mmol/g). These results were higher than those by the grafted monolith with only polymer of PEGA (72% and 81%, respectively) and commercial Wang resin (43% and 39%, respectively). The synthetic efficiency on the grafted monolith with block copolymer in the continuous flow technique was 5–6 folds higher than Wang resins in the manual operation conditions.     

短氟碳链含氟硅烷偶联剂及其疏水涂层的构建

以三氟丙基甲基环三硅氧烷(D3F)、二甲基氯硅烷、甲基二氯硅烷、乙烯基三甲氧基硅烷(VTMS)为主要原料,通过阴离子开环聚合和硅氢加成反应合成了一系列短氟碳链含氟硅烷偶联剂。载玻片表面经纳米二氧化硅溶胶涂膜和硅烷偶联剂表面修饰得到疏水涂层。探究了不同硅烷偶联剂对于涂层疏水性、附着力、硬度、透过率等性能的影响。结果表明,同类型含氟硅烷偶联剂中氟含量越大,其修饰的涂层接触角越大;相似相对分子质量及氟含量情况下,直链型含氟硅烷偶联剂修饰的涂层疏水性优于支链型修饰的涂层。经含氟硅烷偶联剂修饰的疏水涂层中,接触角最大的是由聚合度为9的支链型含氟硅烷偶联剂(DF3)修饰的涂层,可达141.6°。疏水涂层的附着力均达1级,硬度均达H,可见光透过率高于82.9%,具有良好的自清洁性能。     

Grafting modification of ramie fibers with poly(2,2,2-trifluoroethyl methacrylate) via reversible addition–fragmentation chain transfer (RAFT) polymerization in supercritical carbon dioxide

Reversible addition–fragmentation chain transfer (RAFT) polymerization was used to control the grafting of 2,2,2-trifluoroethyl methacrylate (TFEMA) with ramie fibers in supercritical carbon dioxide (scCO₂). The hydroxyl groups of the ramie fibers were converted to 2-dithiobenzoyl isobutyrate as the RAFT chain transfer agent (cellulose-CTA). Then, the subsequent grafting with TFEMA was mediated by RAFT polymerization in the presence of 2-(ethoxycarbonyl)prop-2-yl dithiobenzoate (ECPDB) as the free RAFT chain transfer agent (free CTA). The modified ramie fibers were highly hydrophobic with water contact angles of up to 149°. Size exclusion chromatography showed narrow polydispersity (PDI = 1.28) of the grafted poly(TFEMA) chains. This grafting polymerization process is a novel and environmentally friendly approach for the preparation of functional grafted copolymers utilizing ramie fiber biomass.     

Factors affecting photografting of methacrylic acid on polyethylene film in liquid phases system

Factors affecting photografting (λ > 300 nm) of methacrylic acid on low-density polyethylene film were investigated in liquid-phase system with water. Benzophenone was used as a sensitizer by coating it on the film surface. Factors examined were monomer concentration (1.3 wt% to 10.0 wt%), polymerization temperature (30°C to 70°C), and film thickness (30 μm and 80 μm). It was found that grafted polymer is formed preferentially as compared with homopolymer under conditions such as monomer concentration higher than 6.0 wt%, polymerization temperature higher than 50°C, and film thickness of 30 μm. The structure of the grafted samples obtained in the above systems was characterized by the grafted chains distributing over the film and the flat appearance of film surface. In the grafting systems using the monomer concentration lower than 6.0 wt%, the polymerization temperature lower than 50°C, and the film thickness of 80 μm, homopolymer was formed predominantly. The resultant grafted chains localized mainly on the film surface, which appeared to be grainy.     

Grafting of polystyrene and poly(p‐chlorostyrene) from the surface of ramie fiber via RAFT polymerization

Reversible addition‐fragmentation chain transfer (RAFT) radical polymerization was used for controlled grafting of styrene and p‐chlorostyrene from the surface of ramie fiber. The hydroxyl groups in ramie fiber were first converted to thiocarbonylthio groups as the RAFT chain transfer agent then used to mediate the RAFT polymerization of styrene, and p‐chlorostyrene in tetrahydrofuran using azobis (isobutyronitrile) as initiator at 60°C. The grafted copolymers were analyzed by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetry, and contact angle measurements. The results confirmed that grafting occurred on the surface of the ramie fiber, substantially increasing the water contact angle from 75.31° to 147° for polystyrene grafted ramie fiber (cell‐PS) and 135° for poly(p‐chlorostyrene) (cell‐PSCl), and improving the hydrophobicity of the grafted fiber. The homopolymers formed in the polymerization were analyzed by size exclusion chromatography to estimate the molecular weights and polydispersity indices (PDIs) of chains grafted from the surface of the ramie fiber, as well as showed narrow chain length distributions with a PDI of 1.32–1.70. These materials possess potential applications in many advanced technologies. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Poly(N‐isopropylacrylamide) grafting on aluminium to actively switch its surface drag in water

Active control of flow over object surfaces achieved by means of mechanical and/or electrical methods has recently been studied. However, there has been no report on actively switching the surface drag of an object by chemical modification of the object's surface. Poly(N‐isopropylacrylamide) (PNIPA) was grafted onto the surface of an aluminium (Al) substrate via (A) surface‐initiated atom transfer radical polymerization and (B) radical polymerization with an azo‐group surface initiator. The grafting density was 0.19 and 0.15 chains nm^?2, respectively. The water contact angle of the PNIPA‐grafted Al surface reversibly changed between 55° and 82° for (A) and between 42° and 65° for (B) at temperatures of 25 and 40 °C, which was ascribed to the temperature‐responsive, hydrophilic–hydrophobic switching of the grafted PNIPA surface. The PNIPA grafting was applied on the surface of an ogive‐shaped Al model. The normalized dropping speed of the model in water increased 1.1 times at 42 °C in comparison to that at 22 °C. Switching of the surface drag of PNIPA‐grafted Al in water was demonstrated on the basis of the hydrophilicity and hydrophobicity of the grafted Al surface, the switching occurring with a change in temperature. Copyright © 2010 Society of Chemical Industry     

Organic–inorganic hybrid linseed oil‐based urethane oil wood coatings

To prepare alkoxysilane‐functionalized urethane oil (AFUO) using linseed oil, 3‐aminopropyltriethoxysilane (APTES) was first reacted with diisocyanate to obtain an NCO‐terminating oligomer. The reaction was continued by adding linseed oil glyceride to form an AFUO prepolymer. The auto‐oxidative drying coating was obtained after adding a metal dryer to the AFUO prepolymer. Urethane oil (UO) coating, as a control, was obtained by the same procedure as that for AFUO, but without containing alkoxysilane‐functional groups in the formation. Siloxane hybrid urethane oil (SHUO) wood coatings were prepared by mixing tetraethyl orthosilicate (TEOS) solutions, as an external crosslinking agent by sol–gel process, with the AFUO and UO coatings. We found that introducing of APTES into the molecular chains of the UO coating resulted in a film with superior impact and abrasion resistance, and it is the most efficient process to enhance the UO films. The addition of TEOS into AFUO coatings shortened the curing time and further improved the crosslinking density of the AFUO films; however, the physical properties like impact resistance, bending resistance, and gloss were even worse than AFUO films. Mixing of TEOS and UO coating also shorten the curing time and improved the heat resistance, lightfastness, and hardness of the UO coating. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44562.     

Surface modification of polyurethane by plasma-induced graft polymerization of poly(ethylene glycol) methacrylate

A new approach, plasma-induced graft polymerization of poly(ethylene glycol) methacrylate (PEGMA), was used to introduce PEG graft chains with hydroxyl end groups onto a polyurethane (Tecoflex) surface. After argon plasma treatment and subsequent exposure to air, graft polymerization onto Tecoflex films was allowed to proceed in deaerated aqueous solutions of PEGMA at 60°C. The virgin, plasma-treated, and grafted films were characterized comparatively by means of attenuated total reflection infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, measurement of contact angle, and protein adsorption. The Tecoflex film undergoes etching during argon plasma treatment, surface oxidation when exposed to air after plasma treatment, and surface restructuring in response to environment upon storage in air. The plasma-induced graft polymerization of PEGMA proved to be successful in introducing PEG graft chains with reactive hydroxyl end groups onto the surface. Grafted films with different surface grafting density of PEG were prepared. Grafted films with higher PEG content exhibit higher hydrophilicity, smoother topography, and lower fibrinogen adsorption. The hydroxyl end groups built onto the surface offer further possibilities of improving its biocompatibility by immobilizing bioactive molecules. © 1996 John Wiley & Sons, Inc.