新型聚天门冬氨酸酯合成脂肪族聚脲涂层

通过端氨基聚醚(T403)和马来酸二乙酯的Michael加成反应,合成了新型聚天门冬氨酸酯(PAE-F)。将PAE-F与六亚甲基二异氰酸酯(HDI)三聚体常温聚合,制备了新型聚天门冬氨酸酯(PAEs)聚脲涂层。采用FT-IR和元素分析表征了PAE-F。并用FT-IR和WAXD考察了PAE-F聚脲涂层的形态结构、反应活性和力学性能。与现有的几种PAEs相比,PAE-F与异氰酸酯组份的反应活性更低,凝胶时间为55 min~60 min。结构形态研究表明,PAE-F聚脲呈现非晶形态;氨基氢键化程度高,脲羰基总氢键化程度为57.2%,其中完善氢键化程度为63.1%。这种纯硬段聚脲涂层的强度和硬度高,具有一定的弹性。     

聚酰亚胺薄膜气相沉积的研究进展

综述了气相沉积聚合设备、制备过程、影响因素、性能表征方法及近年来国内外的研究现状.气相沉积聚合聚酰亚胺薄膜相比于传统湿法成型具有纯度高、无溶剂、膜厚可控、致密均匀、可在复杂表面成型等优点.展望了气相沉积的应用以及今后的发展前景.     

有机硅改性喷涂聚脲的性能研究

通过甲苯-2,4-二异氰酸酯(TDI)与羟基硅油反应制备端NCO含硅预聚体,并与经过TDI、己二异氰酸酯(HDI)和聚醚多元醇合成的端NCO预聚体进行共混,得到喷涂聚脲的A组分,再与含聚醚胺的B组分反应制备出有机硅改性喷涂聚脲.对产物结构进行红外光谱表征,并对有机硅改性喷涂聚脲的力学性能、耐水性、接触角和热性能进行了测定.结果表明有机硅改性喷涂聚脲具有良好的的力学性能和热稳定性,防水性能和耐沾污性均得到提高,其中4％质量分数的有机硅改性喷涂聚脲综合性能最佳,吸水率为1.86％,水接触角为103.38°,达到了疏水材料的标准.     

聚对苯(撑)二甲基膜的化学气相沉积(CVD)聚合

采用化学气相沉积(CVD)聚合工艺制备的对苯撑二甲基聚合物可广泛应用在航天、航空、军工、电子、生物医学工程、控制系统、文物保护、纳米材料和磁性材料等诸多领域.综述了聚对苯(撑)二甲基系列膜的化学气相沉积聚合工艺和原理,介绍了底物温度和沉积舱压力等主要因素对膜沉积率的影响和膜的一些主要性能,并讨论了典型的Parylene N膜的光氧降解性能.     

制备过程参数对石蜡-聚脲相变微胶囊性能的影响

以质量比为3:7的固体石蜡和液体石蜡制备的复合石蜡为微胶囊的芯材,以甲苯-2,4-二异氰酸酯和乙二胺为单体,辛基酚聚氧乙烯醚为乳化剂,采用界面聚合法在复合石蜡表面包覆聚脲制备石蜡-聚脲相变微胶囊,探讨乳化转速、乳化剂用量和聚合反应温度对石蜡-聚脲相变微胶囊粒径、包覆效率及蓄热性能的影响。结果表明,在乳化转速为2000r/min,乳化剂与复合石蜡的质量比为0.06,反应温度为70℃的条件下制备的石蜡-聚脲相变微胶囊的平均粒径为3~4μm,熔点为28.1℃,相变潜热为58.4 k J/kg,包覆效率为87.5%。     

水性光固化聚脲的制备与性能研究

优化马来酸二乙酯改性己二胺反应条件，并与异氰酸酯丙烯酸乙酯(AOI)反应，制备了含端双键的一元胺，采用异佛尔酮二异氰酸酯(IPDI)、聚醚胺(PEA,数均分子量M_n约2000)、改性己二胺、二乙基甲苯二胺(DETDA)、乙二胺基乙磺酸钠盐(AAS盐)为主要原料，制备了一系列水性光固化聚脲。采用红外光谱(FT-IR)、核磁氢谱(¹H-NMR)对合成树脂的结构进行了表征探究，采用纳米粒径分析仪、紫外分光光度计、光学接触角测量仪、热重分析仪等手段对乳液和涂膜进行一系列测试表征。结果表明：制备了水性光固化聚脲树脂，其中脂肪族聚脲树脂体系的乳液以及热稳定性更好，芳香族聚脲树脂体系的基本性能更好。     

酰胺扩链剂对聚脲扩链反应动力学的影响

采用红外光谱(FT-IR)技术研究了新型位阻型酰胺扩链剂二乙酰乙二胺(MEDA)和二乙酰己二胺(MHAD)与4,4′-二苯甲烷二异氰酸酯(MDI)的扩链反应。考察了酰胺扩链剂对聚脲凝胶时间的影响,得出酰胺扩链剂能大大延长聚脲的凝胶时间,有利于反应动力学分析。扩链反应动力学研究结果表明,脂肪族酰胺扩链剂合成聚脲的扩链反应中,在反应初期低转化率时,反应均遵循二级动力学关系,得出MEDA和MHAD合成聚脲反应的活化能Ea分别为36.81 kJ/mol和43.99kJ/mol;MEDA反应活性高于MHAD.     

纳米金属包覆材料研究进展

纳米金属材料的表面包覆和修饰是纳米材料学的一个新型研究方向。其制备方法主要有物理吸附法、表面沉积法、电弧放电法、等离子体聚合法、激光化学气相沉积法、乳液聚合法等。包覆结构主要用透射电镜直接观测和成分对比分析等间接手段表征。由于其独特的性质,主要应用在陶瓷增韧、双金属粉末和非线性光学性质等方面。     

纳米结构材料的模板合成方法

本文综述了以径迹蚀刻聚合物膜或多孔Ａｌ２Ｏ３膜为模板,结合电化学沉积、化学沉积、现场聚合、溶胶－凝胶法和化学气相沉积技术合成导电聚合物、金属、碳、无机半导体等纳米管状或线型材料的方法。同时还介绍了模板合成材料的应用前景。     

石蜡/聚脲相变微胶囊的制备及表征

以固体石蜡和液体石蜡熔融混合进行复配,复合石蜡的相变温度和相变焓都随固体石蜡含量的增加而升高,以固液比3∶7制备的复合石蜡熔点为28.3℃,相变潜热为100.04kJ/kg。以此复合石蜡作为微胶囊的芯材,以甲苯2,4二异氰酸酯(TDI)和乙二胺为单体,OP-10为乳化剂,采用界面聚合法在复合石蜡表面包覆聚脲囊壁材料制备石蜡/聚脲相变微胶囊,用扫描电镜(SEM)观察了乳化搅拌速度和反应温度对相变微胶囊表面形貌的影响,并用红外光谱(FTIR)、热重(TG)和差示扫描量热法(DSC)对相变微胶囊进行了表征。实验结果表明:在乳化搅拌速度2000r/min、反应温度70℃时制备的石蜡/聚脲相变微胶囊颗粒呈球形分布,平均粒径在3~4μm范围内,分散均匀,颗粒表面光滑、致密,熔点为28.1℃,相变潜热为58.4kJ/kg,包覆效率为87.5%。     

Polyurea thin film ultrasonic transducers for nondestructive testing and medical imaging

Ultrasonic transducers using polyurea piezoelectric thin film are studied in this paper. Aromatic polyurea thin films, prepared by vapor deposition polymerization, have useful characteristics for use as an ultrasonic transducer. This paper presents the fabrication and experimental evaluation of ultrasonic transducers formed using polyurea films. First, the vapor deposition polymerization process using two monomers is briefly reviewed, and the temperature conditions for higher piezoelectric constants are explored. Second, in order to test the fundamental characteristics of this material as a high-frequency, ultrasonic transducer, a polyurea film of 2.5 microm thickness was deposited on a silicon substrate. In the pulse/echo experiment results, a resonant frequency of about 100 MHz was observed. Third, we fabricated a concave point focus transducer and a cylindrical line focus transducer. To examine the performances of the focus transducers, two-dimensional images of a coin and V(z) curve measurements for an aluminum surface were demonstrated.     

以高岭石稳定的Pickering乳液为模板制备高岭石聚脲微胶囊及相变性能研究

相变微胶囊以其优异的储热性能被广泛用于建筑节能等领域,但是,由于传统相变微胶囊常以表面活性剂所稳定的乳液为模板,由单一高分子聚合物形成囊壁,导致其热稳定性和储热性能较低。本文通过在高岭石稳定的水/石蜡乳液界面处引发异佛尔酮二异氰酸酯和水发生聚合反应,成功获得了囊壁为高岭石聚脲包封客体为石蜡的相变微胶囊。结果表明:相变微胶囊形貌规整呈球形,微胶囊平均粒径为42μm并可通过调控乳液液滴大小实现尺寸调控;该微胶囊的石蜡包封率达85.3%,相变点为49.6℃,热分解温度为218℃,相变潜热高达175.7 J/g。以高岭石稳定的Pickering乳液为模板所制备的相变微胶囊具有良好的热稳定性和相变潜热,有望作为相变储热材料应用于节能领域。     

SiOx包装阻隔薄膜的发展现状及其制备方法

SiOx阻隔薄膜具有优异的阻隔性,并且光透过性和微波透过性好,在阻隔包装领域的应用前景广泛,介绍了SiOx包装阻隔薄膜的制备方法:物理气相沉积,等离子体聚合及大气下等离子体聚合等.     

Molecular layer deposition of functional thin films for advanced lithographic patterning

Photoresist materials comprise one of the main challenges faced by lithography to meet the requirements of electronic device size scaling. Here we report for the first time the use of molecular layer deposition (MLD) to produce photoresist materials with controllable placement of functional moieties. Polyurea resists films are deposited by MLD using urea coupling reactions between 1,4-phenylene diisocyanate (PDIC) and ethylenediamine (ED) or 2,2'-(propane-2,2-diylbis(oxy))diethanamine (PDDE) monomers in a layer-by-layer fashion with a linear growth rate, allowing acid-labile groups to be incorporated into the film at well-controlled positions. The films are deposited with stoichiometric compositions and have highly uniform surface morphology as investigated using atomic force microscopy. We show that acid treatment can cleave the backbone of the polyurea film at positions where the acid-labile groups are embedded. We further show that after soaking the polyurea film with photoacid generator (PAG), it acts as a photoresist material and we present several UV patterning demonstrations. This approach presents a new way to make molecularly designed resist films for lithography.     

Real-time in-situ observation of vapor deposition polymerization of N-methylolacrylamide with IR-RAS

The process of vapor deposition polymerization (VDP) of N-methylolacrylamide (NMAA) was real-time in-situ observed with infrared reflection absorption spectroscopy. The red-heated filament was used for production of the initiator for polymerization. The sticking coefficient and the polymer yield were calculated on the basis of plots of absorbance of C=O and C=C stretching peaks against time during and after the deposition. The sticking coefficient of NMAA molecules on the substrate maintained at 265 K was 0.53 in the case of physical vapor deposition without existence of the red-heated filament. This value reached 0.98 on heating the filament up to 2300 K. The polymer yield in the steady state of VDP was 44%, of which 26% and 18% were caused by the polymerization at the same time as deposition and the post-polymerization, respectively.     

聚硅氧烷-聚脲多嵌段共聚物形态结构的研究

本文采用广角X光衍散(WAXD)表征了在聚硅氧烷软段引入极性氰丙基对聚脲硬段结晶性能的影响。并进一步利用小角X光散射(XAXS)研究了软段极性基团对改善两相相容性的作用以及聚脲硬段分子量对相分离的影响。 结果表明,聚(氰丙基、甲基)硅氧烷聚脲的两相相容性较聚二甲基硅氧烷聚脲有明显改善,两相界面区域增加。随着两相相互作用加强,“硬段微畴”趋于减小且分散均匀,硬段结晶性随软段极性基团的引入而下降。     

Morphologies and release behavior of polyurea microcapsules from different polyisocyanates

Polyurea microcapsules were prepared by emulsion polymerization after adding an aqueous solution with poly(vinyl alcohol) as protective colloid into an organic solution with migrin oil as core material, 1,4-diamino anthraquinone (DAA) as penetrator, and different molar ratios of isophorone diisocyanates (IPDI) and toluene diisocyanates (TDI) as wall materials. The effects of diisocyanate types on the morphologies and release behavior of the resultant microcapsules were investigated. The transmittance (%) of the completely dissolved microcapsule in dimethyl acetamide (DMAc) by UV/visible spectrophotometer decreased with the content of aliphatic IPDI in the wall by increasing the wall thickness due to its inferior reactivity compared to aromatic TDI. Also in SEM images, these polyurea microcapsules from higher TDI content had rougher surfaces. In conclusion, the release profiles of the microcapsules in extraction solution showed that release rate of DAA depended on the roughness of the microcapsules.     

Fabrication and characterization of microcapsules with polyamide–polyurea as hybrid shell

Well-defined microcapsules with polyamide–polyurea as a hybrid shell have been described for biomedical applications. Interfacial polymerization method with surfactant and cosurfactant was developed for the preparation of the hybrid microcapsules. After reaction, centrifugation, and freeze drying processes, the polyamide–polyurea hybrid microcapsules with porous membranes were successfully fabricated. Compared with previous researches of the single polyamide or polyurea microcapsules, experimental data showed that the hybrid microcapsules have a thicker shell and excellent mechanical property. Various diameters and morphologies for the hybrid microcapsules can be obtained by changing the stirring rate, drying method, and surfactant content.     

新型芳香聚脲准轮烷的合成与表征

以4,4′-二氨基二苯醚的-βCD包合物和甲苯-2,4-二异氰酸酯为单体,N,N-二甲基乙酰胺为溶剂,在室温合成了聚脲-βCD准轮烷(3a)。采用红外光谱(FT-IR)、热失重(TG)、核磁共振(1H-NMR)和X射线粉末衍射等手段分别对包合物和准轮烷(3a)进行了表征。结果表明,准轮烷(3a)链上-βCD的含量为42.9%(质量分数),热稳定性良好,是一类新颖的准轮烷。