Synthesis and application of fluorescently labeled phthalic anhydride (PA) functionalized polymers by ATRP

Fluorescent PMMAs containing a phthalic anhydride (PA) group at the chain ends were prepared using the newly developed initiator 7 by atom transfer radical polymerization and subsequent pyrolysis. These polymers allowed for the detection of inter-macromolecular reaction in reactive polymer blends at a low concentration by the use of fluorescence-gel permeation chromatography. The PA-amine coupling reaction proved to be efficient in reactive blending studies for the compatibilization of PS-PMMA blends at low concentration (≤8%) giving a morphology where the average PMMA drop size is 0.6 μm. With 7-nitrobenz-2-oxa-1,3-diazole (NBD) groups as the fluorescent label, the blend morphologies could be visualized in three dimensions by laser confocal microscopy.     

石墨作为润滑油添加剂研究进展

石墨因其特殊的层状晶体结构而被广泛的应用于润滑领域。石墨润滑材料已从单一的石墨颗粒扩展到多种石墨衍生物。在详细总结众多研究成果的基础上综合论述了石墨润滑油添加剂的种类,分散稳定性以及影响其润滑效果的因素,为石墨润滑材料的开发与应用提供参考。     

无硫磷三嗪杂环衍生物润滑油添加剂的制备及摩擦性能

以三聚氯氰和吗啉、苯酚为原料合成了两种无硫磷的三嗪含氮杂环衍生物2,4,6-三吗啉基-均三嗪（CMMM）和2,4,6-三苯酚基-均三嗪（CPPP）润滑油添加剂,并采用FT-IR和元素分析对其结构进行了表征。考察了CPPP和CMMM的热稳定性和油溶性。采用四球摩擦磨损试验机研究了CMMM和CPPP在菜籽油中的极压、抗磨及减摩性能;并测试了CMMM和CPPP分别与T202进行复配后的摩擦学性能。采用SEM和EDS观察摩擦表面的形貌特征和元素。结果表明,合成了目标产物CMMM和CPPP;CMMM和CPPP在菜籽油中具有良好的溶解性;在相同实验条件下,CMMM和CPPP的分解温度范围分别为270.16~347.58℃和285.26~478.45℃。两者具有良好的热稳定性,且CPPP的热稳定性优于CMMM;在不同的载荷、添加比例等条件下,CPPP的摩擦学性能优于CMMM。CPPP优异的摩擦学性能得益于分子中含的苯酚环比吗啉环更加紧密,在摩擦过程中,添加剂与摩擦副表面发生化学反应,生成了含氮的复合边界润滑膜,起到减摩抗磨的作用。复配性能测试发现,在不同的载荷、添加比例等条件下,CMMM与T202的最佳复配比为5:5,CPPP与T202的最佳复配比为3:7。     

Antimicrobial effect of monomers and polymers with azole moieties

Five monomers with azole moieties were synthesized and their antimicrobial activities were investigated. The antimicrobial activity of the monomers was evaluated by the halo zone test method. The results strongly depended on the chemical structure of the group attached to the azole moieties. Polymers with (benzimidazol‐2‐yl)thio groups and with (5‐methyl‐1,3,4‐thiadiazol‐2‐yl)thio groups were synthesized. The shake flask test showed that the two polymers possessed excellent antimicrobial activity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2933–2937, 2003     

Synthesis and characterization of novel photoconducting carbazole derivatives in main-chain polymers for photorefractive applications

We have prepared hole-transporting polymers that have carbazole and 3,3′-dicarbazole in the main chain by polycondensation based on Fridel-Craft reaction via cations generated by proton of p-toluene sulfonic acid catalyst. In the device, they display high diffraction efficiency at low external electric field. The DiCz composite had a high diffraction efficiency of 82.4% at 52 V/μm and a photorefractive response time constant of 1.18 s at an electric field of 50 V/μm and a writing intensity of 60 mW/cm². The samples have excellent properties with respect to optical quality and shelf-lifetime.     

Synthesis and applications of stimuli-responsive hyperbranched polymers

Benefiting from their responsiveness and adaptability, the stimuli-responsive polymers have been widely investigated and exploited in the various fields, such as environmental monitoring, electronics, photonics, controlled drug delivery, medical imaging and diagnostics. These potential applications have greatly promoted the development of advanced functional materials, and meanwhile set higher requirements for the smart materials in the aspects of the spatial structures, diverse linkages and variable functions. However, the linear functional polymers can not satisfy all the requirements of the multi-dimensional molecular design and acute sensitiveness due to the architectural limitation. Accordingly, stimuli-responsive hyperbranched polymers (HBPs) have been drawing more and more attention in recent years owing to their unique globular void-containing topological structure featured with a large number of terminal functional groups and branches, lower solution or melt viscosity, and better solubility. Therefore, design and synthesis of stimuli-responsive HBPs provide a robust tool for controlling the structure transition and creating the hierarchical sensitivity driven by different triggers. In this review, the developments and recent advances of preparation procedures, performance control and promising applications of various stimuli-responsive HBPs have been comprehensively summarized. Besides, the developing trend of stimuli-responsive HBPs is also discussed. It can be found that stimuli-responsive HBPs with different synthetic strategies and diverse performances have manifested more and more versatile applications.     

新型防锈润滑添加剂的合成研究

以柠檬酸、壬基酚聚氧乙烯醚和二乙醇胺为原料合成了一种具有防锈、润滑双重功能的水基合成切削液添加剂———柠檬酸壬基酚聚氧乙烯醚单酯二乙醇酰胺。柠檬酸酐的制备条件为柠檬酸∶乙酸酐(摩尔比)为1.0∶1.2,温度为35℃,反应时间为18h;酯化摩尔比(酸酐∶OP)为1.0∶1.2,温度为80~90℃,反应时间为3h;酰胺化条件为柠檬酸壬基酚聚氧乙烯醚单酯∶二乙醇胺(摩尔比)为1∶1.5,反应温度为130~140℃,反应时间为3~4h。采用红外光谱法对产物进行表征,进而确定了合成的最佳工艺路线和工艺条件。     

Synthesis and characterization of new hyperbranched polymers with only inner functional groups modified

The novel core‐shell polymers were synthesized based on the perfluoroalkyls grafting onto the inner hydroxyl groups of hyperbranched polyglycidol while the outer hydroxyl groups remained unaffected. The samples were characterized with FTIR, NMR, element analysis, and liquid chromatography/mass spectrometry. The various results obtained by different measurements are in good agreements. The conversion ratio of inner hydroxyl groups is about 0.3 and most functionalizations took place in linear 1,4‐units (L_1–4). Differential Scanning Calorimetry results suggest the samples are amorphous within the experiment range. Their inner lipophilicity and outer hydrophilism resulted from their unique structures are expected to gain promising applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 317–322, 2006     

开式齿轮润滑剂应用研究(一)

综述分析了目前所研制的溶剂沥青型、半流体脂及高粘度油这三种润滑剂性能、不同配方下的特点等。现场试验结果证明,这三类润滑剂均可满足开式大齿轮的防护要求。同时,分析了影响润滑剂选择的各种因素,并对不同润滑剂在成本和使用性能方面的差异进行了比较。     

疏水缔合水溶性聚合物的合成与表征

综述了疏水缔合型水溶性聚合物合成与表征方法，介绍了在合成过程中提高油溶性单体和水溶性单体混溶性的方法，简述了疏水物质含量的核磁共振、紫外光谱、裂解气相色谱等测定方法。     

Photocuring of cycloaliphatic epoxy formulations using polyesters with multiarm star topology as additives

Multiam star polyesters were synthesized by growing poly(ε‐caprolactone) (PCL) arms from hyperbranched polyesters cores of different molecular weight and used as polymeric modifiers in UV‐curable cationic formulations based on a biscycloaliphatic epoxy resin. The effect of the multiarm stars on the curing kinetics has been investigated by real‐time FTIR. The thermal‐mechanical properties of the photocured thermosets have been studied with calorimetry and dynamomechanical and thermogravimetric analysis. Impact strength tests have been performed to assess their effect on the toughness of the cured materials. An accelerative effect of these modifiers has been observed as a consequence of the participation of the hydroxyl groups of the modifiers in the cationic curing of the epoxy resin. A modest increase in toughness accompanied by a decrease in the glass transition are observed, as a consequence of the incorporation of the modifiers into the network structure, leading to homogeneous, in situ reinforced materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40005.     

减摩抗磨类新型润滑油添加剂的研究进展

减摩抗磨类润滑油添加剂能提高基础润滑油的摩擦学性能使其在润滑领域具有广阔的应用前景,但是商用润滑油添加剂大多含有P、S等有害元素,因此,寻找更加环保、经济的润滑油添加剂具有重要意义。本文根据润滑油添加剂结构种类和润滑机理的不同,以及国内外各种润滑油添加剂在润滑方面的相关成果,综述了近年来纳米颗粒(纳米单质及其复合颗粒、纳米氧化物、纳米硫化物、纳米氮化物)、含氮杂环化合物及其衍生物、硼酸酯及其衍生物、离子液体等添加剂的合成方法以及在减摩抗磨方面的应用,并对其发展状况和减摩抗磨机理进行了探究。指出了其润滑机理主要为吸附膜机理、摩擦反应膜机理和滚珠机理。最后对其存在的问题进行分析,提出了当前润滑领域研究的热点和方向依然是复合添加剂的制备和机理探究。     

Rheological cure characterization of phosphazene–triazine polymers

Cyclomatrix phosphazene–triazine network polymers were synthesized by co‐curing a blend of tris(2‐allylphenoxy), triphenoxy cyclotriphosphazene (TAP), and tris(2‐allylphenoxy) s‐triazine (TAT) with bis(4‐maleimido phenyl) methane (BMM). The co‐curing of the three‐component resin was investigated by dynamic mechanical analysis using rheometry. The cure kinetics of the Diels–Alder step was studied by examining the evolution of the rheological parameters, such as storage modulus (G′), loss modulus (G″), and complex viscosity (η*), for resins of varying compositions at different temperatures. The curing conformed to an overall second‐order phenomenological equation, taking into account a self‐acceleration effect. The kinetic parameters were evaluated by multiple‐regression analysis. The absence of a definite trend in the cure process with blend composition ratio was attributed to the occurrence of a multitude of competitive reactions whose relative rates depend on the reactant ratio and the concentration of the products formed from the initial phase of reaction. The cure was accelerated by temperature for a given composition, whereas the self‐acceleration became less prominent at higher temperature. Gelation was accelerated by temperature. The gel conversion decreased with increase in maleimide concentration and, for a given composition, it was independent of the cure temperature. The activation energy for the initial reaction and the crosslinking process were estimated for a composition with a maleimide‐to‐allyl ratio of 2 : 1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 908–914, 2003     

Synthesis and characterization of thermally stable polymers (polybenzimidazoles)

In this study, an alternative synthesis of polybenzimidazoles was performed with aromatic hydroxamoyl chloride. In contrast to the literature, polybenzimidazoles were obtained through the reaction of hydroxamoyl chlorides with 3,3′‐diaminobenzidine or 1,2,4,5‐tetraaminobenzene. The characterization of the polymers was performed with Fourier transform infrared, ¹H‐NMR, elemental analysis, LC mass spectrometry, and differential thermogravimetry/thermogravimetric analysis. Finally, the adhesion, corrosion resistance, and conducting properties of the synthesized polymers were examined. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Structural considerations and new polymers for biomedical applications

Polymers intended for surgical implantation must satisfy the double requirement of adequate long-term mechanical properties and surface compatibility. Earlier concepts of intertness are being modified to ascribe a more interactive role to polymers mainly resulting from studies on blood compatibility and controlled drug release. The interfacial reactions implied by interactive behaviour determine immediate compatibility whereas longer-term functional acceptance is more related to bulk properties. The relationship between these two requirements in terms of polymer structure is discussed with reference to new polymers in use, studies of polymer orientation and uses of polymer composites containing carbon fibre. Structural order is an important consideration for biomedical applications and when this is achieved in conjunction with composites, interesting developments are possible.     

Synthesis and characterization of polyarylureas. I. Potentially semiconducting polymers

Polyarylureas were synthesized from the reaction between phosgene with aromatic diamines. Depending on the pH, the polyarylureas presented different colors when the solvent used was pyridine. The polyarylureas were characterized by IR spectroscopy, elemental analysis, and X‐ray photoelectron spectroscopy (XPS). To study the thermal stability of the polymers, a thermal degradation was performed between 35 and 700°C. The polyarylureas decomposed above 350°C. Without doping, polyarylureas are considered as semiconductors [σ = 10^?9 (Ωcm)^{? 1}]; after doping with I₂, their electrical conductivity increases by several orders of magnitude. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 822–830, 2001     

Synthesis,characterization, and studies on the solid-state crosslinking of functionalized vinyl cinnamate polymers

Functionalized vinyl cinnamate monomers were synthesized by the reaction between hydroxyethylacrylate (HEA) and substituted cinnamoyl chlorides possessing electron releasing and withdrawing functional groups like chloro, methoxy, and nitro groups at the para position of the aromatic ring. The structures of these monomers were characterized by Fourier transform infrared (FTIR), ¹H-, and ¹³C-NMR spectral techniques. The homopolymers of the synthesized monomers were obtained by the free radical solution polymerization in dimethylformamide (DMF) at 80°C for 12 h using azobisisobutyronitrile (AIBN) as a radical initiator. The sensitivity of these polymers towards light was studied by monitoring the photocrosslinking nature of the polymers by ultraviolet (UV) and FTIR techniques. The effect of the functional groups on the crosslinking efficiency was studied and compared with that of the unsubstituted polymer. The cyclobutane-type addition mechanism involved in the photocrosslinking phenomena was confirmed by the above spectral studies in the functionalized vinyl cinnamate polymers. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 441–448, 1998     

Synthesis and characterization of high molecular weight water-soluble polymers

The synthesis of high molecular weight acrylic water-soluble polymers in heterophase water-in-oil polymerizations is discussed. A mechanism has been elucidated which includes elementary reactions in the continuous (organic) and dispersed (aqueous) phases, as well as the interfacial layer. The latter allows for the identification of interfacially active species which can concurrently enhance stability and increase the linear molecular weight of the polymer. Suitable species are found to contain multiple radically active functional groups on either the hydrophilic or hydrophobic moieties. A one-point light-scattering method is also developed which improves the accuracy in molecular-weight estimation to /pi5%. compared with /pi10% for the conventional dilution procedure. This is demonstrated for high molecular weight polyacrylamides and is found to reduce the sample measurement time fourfold, to 20 min.