含杂环聚芳醚腈酮的亲水改性

为得到适合于耐高温水性涂料用的亲水性树脂,在碱性条件下对含有二氮杂萘酮结构的耐高温聚合物聚芳醚腈酮(PPENK)进行了亲水改性,选定不同反应时间的改性树脂HPPENKa(0.5 h)、HPPENKb(1.5 h)和HPPENKc(3.5 h),测定其玻璃化转变温度(Tg)、热失重温度、水接触角和溶解性,研究改性聚合物的性能变化.结果表明,随着反应时间的延长,氰基转化率提高,水解产物Tg增加,热失重温度有所降低,水解前后的溶解性能有很大变化,亲水性能明显增强,例如,当氰基转化率为93.82%时,HPPENK膜的水接触角达到54.4°,比PPENK膜的水接触角(75.3°)减小了20.9°.同时,甄选不同的反应共溶剂、反应温度以及碱浓度,考察其对反应的影响,结果表明,当反应温度为120℃6、mol/L NaOH溶液、以DMAc作为反应的共溶剂时对反应较为有利.制备了基于3种改性树脂的水分散体,其静置稳定性依次为HPPENKc>HPPENKb>HPPENKa,其中HPPENKc水分散体较稳定,30天内未出现沉淀.改性聚合物的结构经FT IR和1H-NMR表征.     

自由体积与亲水性对环氧涂层防护性能的影响

报道了涂层聚合物自由体积和亲水性对涂层腐蚀防护性能影响的初步研究结果.实验表明,相对于自由体积,树脂的亲水性是决定树脂吸水率的更主要因素.低亲水性涂层腐蚀防护性能的提高主要源自到达涂层/金属界面的水量的显著降低.但由于采用活性酯固化的环氧树脂涂层中水通道的尺寸相对较大,水合离子扩散较容易,因此该类涂层覆盖下的金属基体被润湿部分的腐蚀趋势反而较一般涂层为大.     

低聚端羟基聚硅氧烷接枝增韧酚醛树脂的制备及性能

由低聚羟基封端聚硅氧烷（HO-PDM）与甲醛和苯酚的接枝反应制备了增韧改性酚醛树脂,用FT-IR对改性酚醛树脂的结构进行表征,用电子万能试验机测试了改性前后酚醛树脂的力学性能,用热重分析仪测试改性酚醛树脂的热稳定性。 测得改性酚醛树脂的断裂伸长率、冲击强度、抗拉强度分别为2.8%、2.875 kJ/m2和23.2 MPa;树脂失重20%的温度为431.28 ℃,峰值温度为441.8 ℃,800 ℃的残重率为51.02%。     

二氧化硅纳米颗粒/硅树脂复合超疏水功能涂层的制备和性能研究

将二氧化硅纳米颗粒和硅树脂制成混合液,采用喷涂法(spray-coating)制备出了具备超疏水性的复合涂层.研究了二氧化硅、硅树脂不同含量配比对涂层疏水性能的影响,结果表明复合涂层的接触角随二氧化硅含量的增加而增加.在二氧化硅含量大于3%(质量分数)时,涂层显现超疏水性;当二氧化硅含量为3%(质量分数)、硅树脂含量为7%(质量分数)时,涂层与水的接触角达到151.6°,滚动角接近0°.通过扫描电子显微镜(SEM)观察涂层表面的微观结构,发现超疏水性的涂层具备微-纳复合阶层结构,类球状突起粒径在5μm左右,类球状突起上分布纳米团聚颗粒,直径约为50 nm.这种类似荷叶表面的微(纳复合阶层结构,结合硅树脂的低表面能,使得复合涂层具备了超疏水性能.     

In situ formed silica nanofiber reinforced UV-curable phenylphosphine oxide containing coatings

A series of UV-curable nanocomposite coating materials were prepared by sol–gel technique from tetraethoxysilane (TEOS), methacryloxypropyltrimethoxysilane (MAPTMS) in the presence of urethane acrylate resin based on polyethylene glycol 400 (PEG400). The sol–gel precursor content in the hybrid coatings was varied from 0 to 30 wt.%. In addition, acrylated phenylphosphine oxide oligomer (APPO) is replaced with urethane acrylate resin in order to investigate its effect on the nanocomposite property. The physical and mechanical properties such as; gel content, hardness, adhesion, gloss, impact strength as well as tensile strength were examined. Results from these measurements showed that all the properties of the hybrid coatings improved effectively by gradual increase in sol–gel precursor and APPO resin content. The real time infrared technique was used to follow the degree of acrylic double bond conversion. The thermal stabilities of the UV-cured nanocomposites were investigated by thermogravimetric analysis. The results revealed that the addition of sol–gel precursor and APPO oligomer into the organic network leads to an improvement in the thermal and flame resistance properties of the hybrid materials. It was also determined that the APPO containing hybrid coating with 20 wt.% silica content gave higher char yield than the coating without APPO. It is a desirable achievement to improve simultaneously both the flame retardancy and mechanical properties of a protective coating. SEM studies indicated that inorganic particles were dispersed homogenously through the organic matrix. The hybrids were nanocomposite. It was also found that, incorporation of APPO resin might govern the silica organization and this leading to formation of nanofibrillar structure.     

The maleimide modified epoxy resins for the preparation of UV‐curable hybrid coatings

In the present study, maleimide‐modified epoxide resin containing UV‐curable hybrid coating materials were prepared and coated on polycarbonate substrates in order to improve their surface properties. UV‐curable, bismaleimide‐modified aliphatic epoxy resin was prepared from N‐(p‐carboxyphenyl) maleimide (p‐CPMI) and cycloaliphatic epoxy (Cyracure‐6107) resin. The structure of the bismaleimide modified aliphatic epoxy resin was analyzed by FTIR and the characteristic absorption band for maleimide ring was clearly observed at 3100 cm^?1. Silica sol was prepared from tetraethylorthosilicate (TEOS) and methacryloxy propyl trimethoxysilane (MAPTMS) by sol–gel method. The coating formulations with different compositions were prepared from UV‐curable bismaleimide‐based epoxy oligomer and sol–gel mixture. The molecular structure of the hybrid coating material was analyzed by ²⁹Si‐CP/MAS NMR spectroscopy techniques. In the ²⁹Si CP/MAS NMR spectrum of the hybrid coating, mainly two kinds of signals were observed at ?68 and ?110 ppm that correspond to T³ and Q⁴ peaks, respectively. This result shows that a fully condensed structure was obtained. The thermal and morphological properties of these coatings materials were investigated by using TGA and SEM techniques. Hardness and abrasion resistance properties of coating materials were examined and both were found to increase with sol–gel precursor content of the coating. The photopolymerization kinetics was investigated by using RT‐IR. 70% conversion was attained with the addition of 15 wt% of BMI resin into the acrylate‐based coating formulation. It was found that the UV‐curable organic–inorganic hybrid coatings improved the surface properties of polycarbonate. Copyright © 2009 John Wiley & Sons, Ltd.     

Thermal conductivity epoxy resin composites filled with boron nitride

Boron nitride (BN) micro particles modified by silane coupling agent, γ‐aminopropyl triethoxy silane (KH550), are employed to prepare BN/epoxy resin (EP) thermal conductivity composites. The thermal conductivity coefficient of the composites with 60% mass fraction of modified BN is 1.052 W/mK, five times higher than that of native EP (0.202 W/mK). The mechanical properties of the composites are optimal with 10 wt% BN. The thermal decomposition temperature, dielectric constant, and dielectric loss increase with the addition of BN. For a given BN loading, the surface modification of BN by KH550 exhibits a positive effect on the thermal conductivity and mechanical properties of the BN/EP composites. Copyright © 2011 John Wiley & Sons, Ltd.     

Preparation of photocurable silica–titania hybrid coatings by an anhydrous sol–gel process

Photocurable silica-titania hybrid coatings were prepared through an anhydrous sol–gel process. Moreover, test samples were prepared by the addition of definite ratios of fluoro acrylate oligomers into the formulations to manage the optical properties of transmitted light. Formulations were applied to corona-treated polycarbonate substrates. Upon adding the inorganic component to the coating material, thermal, mechanical, and other properties, such as hardness, gloss, contact angle, and flame resistance were improved. The photocured hybrid films showed an increase in the refractive index with increasing the titanium tetraisopropoxide content. As expected, a decrease was observed in the refractive index of the coatings with the incorporation of fluoro acrylate resin. The surface morphology of the hybrid films was characterized by ESEM analysis. In addition the chemical composition of the surface of the coatings was identified by ESEM–EDS technique. ESEM studies indicated that inorganic particles were dispersed homogenously throughout the organic matrix.     

聚苯硫醚超疏水复合涂层的制备与性能

利用工业原料聚苯硫醚微粉和疏水性二氧化硅纳米粉末,采用喷涂法在瓷砖表面制备了疏水复合涂层.研究了热处理温度、组分配比对涂层表面形貌、粗糙度和接触角的影响,发现随着热处理温度升高,涂层表面粗糙度增大,随着疏水性二氧化硅含量的增加,由于表面聚集的疏水性二氧化硅增多,涂层疏水性增强,在热处理温度为280℃、疏水性二氧化硅与聚苯硫醚质量比为1∶1时,可获得超疏水涂层,涂层的接触角大于150°,滚落角小于4°,pH值为1～14的水溶液在其表面都具有很高的接触角.超疏水涂层具有良好的自清洁效果,并且经落沙法实验测定,超疏水涂层耐刮伤性能良好.     

Development and characterization of transparent waterborne polyurethane acrylate/fullerenols thin-film nanocomposite as thermal-insulating coating

Thermal-insulating coating can lower the energy consumption and cooling costs, which caters to the tendency of environmental protection and energy conservation. Transparent waterborne polyurethane acrylate thin-film nanocomposite was developed by incorporating the fullerenol C₆₀(OH)₁₂(ONa)₂ into the system using ultrasonic dispersion. The thin-film nanocomposite was then synthesized by ultraviolet radiation curing and chemical crosslinking, and its morphology and chemical structures were characterized. Thermogravimetric analysis and differential thermal gravity were used to evaluate the thermal stability. The surface and mechanical properties were tested by the pendulum hardness and MEK resistance. The optical and thermal-insulating properties were assessed by the ultravioletvisible-near infrared spectrophotometer and indoor environmental simulation experiment. The thermal-insulating measurements showed that the glass coated thin-film nanocomposite possessed better thermal-insulation effect than empty glass.     

卡拉胶包覆APP微球阻燃水性环氧树脂

以氯化钡提纯k-卡拉胶, 经过氧化氢降解, 通过反相乳液聚合的方式制备了一系列卡拉胶包覆聚磷酸铵(APP)阻燃微球(k-CM/APP); 将其加入到水性环氧树脂(EP)中, 制备了3种钢结构防火涂层EP2, EP3和EP4. 利用红外光谱(IR)、 扫描电子显微镜(SEM)及元素分析(EDS)对k-CM/APP的结构及形貌进行了表征. 利用极限氧指数(LOI)、 垂直燃烧(UL-94)、 背温测试法、 热重分析(TG)、 锥形量热(CONE)、 附着力测试、 IR和SEM等方法分析了涂层的阻燃、 隔热及力学性能. 结果表明, k-CM/APP(3/1)球形结构完整, 800 ℃时的残炭量高达59.5%. 与其它阻燃涂层体系相比, 添加了k-CM/APP(3/1)的EP3防火涂层的极限氧指数达到28.5%, UL-94达到了V-0级, 60 min防火涂层耐火温度为253 ℃. 相比于纯EP涂层, EP3涂层的热释放速率峰值降低了58.26%, 总热释放量降低了20.84%, 附着力达到8.74 MPa.     

The coating performance of adipic acid modified and methacrylated bisphenol- A based epoxy oligomers

In the present work adipic acid modified and methacrylated bisphenol A based epoxy resins were prepared. The structures of oligomers were characterized by FT-IR. UV curable clear coatings were applied on aluminum substrates. The physical and mechanical properties of UV-cured coatings such as gel content, solvent resistance, hardness, gloss, flexibility and tensile tests were examined. In addition, the thermal behavior of coatings was also evaluated. It is observed that the tensile properties and thermal stabilities of modified epoxy methacrylate coatings mainly depend on the adipic acid content. The best results were obtained with 5 wt% adipic acid modification. Copyright © 2007 John Wiley & Sons, Ltd.     

Hollow-glass-microsphere-based Biphenyl Epoxy Resin Composite with Low Dielectric Contant

In this study, rigid 4,4'-diglycidyl(3,3',5,5'-tetramethylbiphenyl) epoxy(TMBP)-based composites were developed by the incorporation of varying percentages of commercial hollow glass microspheres(HGMs, QH-450) into the TMBP resin used for electronic packaging. The thermal and mechanical properties as well as the morphology of all the composites were characterized, and dielectric properties were characterized by advanced analytical techniques. The results reveal that a series of TMBP/QH-450 composites exhibits higher initial degradation temperatures(T_d,5%>300℃), and the residual char and glass transition temperature were clearly improved with QH-450 loading. In addition, all epoxy composites exhibited a lower dielectric constant ranging from 3.74 to 3.06 at 1.2 MHz because the lower dielectric properties of the inert gas used as the core of the QH-450 decreased molecule polarity. Hence, this developed TMBP/QH450 system demonstrates potential applications in electronic packaging.     

水热温度对SiC-C/C复合材料表面水热电泳沉积MoSi2抗氧化涂层的影响

采用水热电泳沉积法和固相渗透法在C/C复合材料表面制备了MoSi2/SiC复合抗氧化涂层。分别采用X射线衍射、扫描电子显微镜和等温静态氧化实验对复合涂层的晶相组成、显微结构和抗氧化性能进行了表征。主要研究了水热电泳沉积温度对MoSi2外涂层显微结构及高温抗氧化性能的影响,重点分析了涂层试样在1500℃和1630℃下的静态氧化行为及失效机理。结果表明:外涂层主要由MoSi2和少量MoO3晶相组成。外涂层的致密程度、厚度及抗氧化性能随着水热温度的升高而提高。MoSi2/SiC复合涂层具有较好的抗氧化和抗热震能力,在1 500℃下有效保护基体320 h同时经历17次1 500℃与室温之间的热循环后,氧化失重率仅为1.07%;在1630℃下氧化88 h后失重率为2.17%。复合涂层在1 630℃下的氧化失效主要是由于经过长时间氧化后SiO2玻璃膜层不能及时有效填补涂层中的缺陷,涂层试样在热循环过程中产生了贯穿性的孔洞导致的。     

Synthesis and properties of iron oxide coated carbon nanotubes hybrid materials and their use in epoxy coatings

Multi‐walled carbon nanotubes (MWCNTs) were acidified with nitration mixture, and the Fe₂O₃‐MWCNTs (iron oxide coated multi‐walled carbon nanotubes) hybrid material via sol‐gel method then verified the results through scanning electron microscope, X‐ray diffraction, and thermal gravimetric analysis. We modified the hybrid material with silane coupling agent (KH560), Fe₂O₃‐MWCNTs/epoxy, MWCNTs/epoxy composites coating, and the pure epoxy coatings were respectively prepared. The properties of the composite coatings were tested through the electrochemical workstation (electrochemical impedance spectroscopy), shock experiments, and thermal gravimetric analysis. Finally, we used scanning electron microscope to observe the surface conditions of the coatings. The results show that Fe₂O₃‐MWCNTs have good dispersion in the epoxy resin, and the Fe₂O₃‐MWCNTs/epoxy composite coatings have enhanced mechanical properties and corrosion resistance. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis, characterization and flame retardant of UV-curable hybrid coatings containing SiO2–P2O5–B2O3 via sol–gel method

A ternary sol containing silicon, phosphorus and boron modified by ??-methacryloxypropyltrimethoxysilane was synthesized by sol?Cgel method. The ternary sol was incorporated into the organic matrix and UV-curable organic/inorganic hybrid coating materials were obtained. Hardness, transmittance, haze, cross-cut adhesion and abrasion resistance results showed that the mechanical properties of the hybrid coatings improved effectively with no comprising on optical properties by increasing sol content. Scanning electron microscopy and Energy Dispersive X-ray spectrometer studies indicated that inorganic particles were homogenously dispersed in the organic matrix. The flame retardancy of the UV-curable coatings was investigated by thermogravimetric analysis and microscale combustion calorimeter. The results showed that the incorporation of sol into the organic network led to an improvement in the thermal stability and flame retardancy of the hybrid coating materials. It is a desirable achievement to improve simultaneously both flame retardancy and mechanical properties of the coatings.     

纳米炭黑复合涂料的制备及其耐蚀性能

纳米炭黑复合涂料的制备及其耐蚀性能;纳米炭黑;复合涂料;制备;耐蚀性     

3-氨丙基三乙氧基硅烷对聚氨酯/Al-Sm_2O_3复合涂层自然老化性能的影响

通过硅烷偶联剂3-氨丙基三乙氧基硅烷(KH550)改性聚氨酯(PU)/Al-Sm_2O_3复合涂层,从功能特性和力学性能角度系统研究了改性前后涂层自然老化性能的变化规律。结果表明,改性后PU/Al-Sm_2O_3复合涂层的红外发射率对自然老化的稳定性得到明显增强,在同等条件下改性后的涂层发射率要明显低于未改性的涂层发射率。改性后涂层表面的Sm_2O_3颗粒分散更加均匀,对近红外光的吸收强度有所增强,从而使改性后涂层对1.06μm近红外光的反射率要明显低于未改性涂层。改性前后涂层的硬度对自然老化具有良好的稳定性,其硬度可保持在3 H;未改性涂层的附着力和耐冲击强度受自然老化影响明显,但改性后涂层的附着力和耐冲击强度得到明显加强,经自然老化4个月后仍然可保持在1级和50 kg·cm。     

Low-density polycarbonate composites with robust hollow glass microspheres by tailorable processing variables

Polycarbonate (PC) composites with low weight have been required for mobile applications. Herein, the incorporation of 15 phr (parts per hundred of resin) soda-lime borosilicate hollow glass microspheres (HGMs) into a PC matrix reduced the specific gravity by 15.2%. The microsphere preservation rate was systematically examined depending on HGM compressive strength, and processing conditions for extrusion (side-feeding vs. main-feeding vs. screw configuration) and injection molding (mild condition for edge gate vs. extreme condition for pinpoint gate). Various transition temperatures such as glass transition temperatures and heat distortion temperature were investigated as a function of HGM. The coefficient of thermal expansion of the 15 phr HGM-embedded PC composites was reduced by 51.9%. The rheological behavior of the composites was also probed. The toughness was reduced due to the ductile-to-brittle transition of PC caused by the incorporation of fillers despite the enhanced modulus. The incorporation of the robust hollow glass microspheres into a PC composite via a delicately designed screw configuration and suitable processing conditions can be used for low-density composites such as mobile applications.     

Preparation and characterization of polyurethane based self-cleaning and antibacterial coating containing silver ion exchanged montmorillonite/TiO<Subscript>2</Subscript> nanocomposite

In order to reach an antibacterial, photocatalytic, and hydrophilic coating, commercial grade polyurethane (CPU) resin was modified with silver ion exchanged montmorillonite/TiO₂ nanocomposite in various montmorillonite to TiO₂ nanoparticle ratios. To characterize the prepared nanocomposites and coatings, X-ray diffraction patterns, FTIR and UV–Vis spectroscopy and SEM images were used. The modified commercial grade polyurethane coatings containing nanocomposites show better properties, including hydrophilicity, degradation of organic pollutants, antibacterial activity and water resistivity, compared to unmodified commercial grade polyurethane coatings. The water droplet contact angle of unmodified CPU coating was 70°, however it decreased to lower than 10° in modified CPU coatings after 24 h LED lamp irradiation. Decolorization efficiency of malachite green dye solution by the use of modified CPU coatings achieved up to 70% after 5 h LED lamp illumination, compared to less than 5% for unmodified CPU coatings. Modified CPU coatings also showed significant water resistivity and antibacterial properties.