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1.
The transformation of solvent soluble unsaturated polyester resins into resins able to form stable water dispersion is presented in this paper. The methods of modification are discussed, consisting of the introduction of polar hydrophilic groups such as carboxylic and sulfonic ones (sodium 5‐sulfonatoisophthalic acid) into the resin molecule, which ensure good tolerance with water. Instead of styrene, glycerol monoethers of allyl alcohol and unsaturated fatty alcohols were used as reactive built‐in crosslinking monomers for resin modification. The influence of the resin composition and method of synthesis on the dispersion stability and properties of photocurable lacquer coatings obtained from the waterborne resins were investigated.  相似文献   

2.
An outline of the history and manufacture of polycarbonate resins is followed by a discussion about resin product types anal their processing. The key properties of flex modulus, deflection temperature, and impact are those that make polycarbonate resins premier engineering resins. Like most other engineering plastics, polycarbonate resins' early commercial history was characterized by substitutions of polycarbonate resins for traditional materials, particularly metal and glass. Examples of applications are presented, More recently application developments involve ab initio selection of polycarbonate resins and article designs based on polycarbonate resin properties. In addition, “tailored” resins such as poly (estercarbonate) resins and polycarbonate resin blends have evolved to meet specific applications. The future growth of polycarbonate resins is predicted to feature few new resins, many new blends, and application developments using computer techniques.  相似文献   

3.
Four polyether and one polyester-modified cationic resins were synthesized by reacting polyether/polyester-modified epoxy resins with 2-ethylhexanol-blocked-toluene diisocyanate (2-EH-blocked TDI) and diethanolamine and subsequently neutralizing the resins with acetic acid. Four different polyethers and one polycaprolactone diol (PCP) were used to react with epoxy resin to form polyether-modified epoxy resins (1a–d) and polyester-modified epoxy resin (1e). The extent of reaction of epoxy resin and polyether or polyester was evaluated by the change of epoxy equivalent weight and the gel permeation chromatography curve of the resulting product. Cationic resins were dissolved in suitable solvents and were mixed with deionized water to form emulsions. Some factors, such as pH value of emulsion, solvent content, and applied voltage affecting the emulsion and electrodeposition properties, were investigated. Cationic resins, prepared from PPG (#1000)-modified epoxy resins, yielded a wider pH range of stable emulsion and also yielded deposited films with a pleasing appearance. PEG (#1000)-modified cationic resins produced a higher deposition yield, but higher throwing power was obtained by deposition of the PCP (#530)-modified cationic resins.  相似文献   

4.
Aniline-modified epoxy resin which contains tertiary amine in the middle of the polymer chain was synthesized by the reaction of aniline and epoxy resin. The resulting aniline-modified epoxy resin and two commercial epoxy resins with different epoxy equivalent weights were reacted with 2-ethylhexanol-blocked toluene diisocyanate (2-EH-blocked TDI) to obtain thermally crosslinkable epoxy resins. These epoxy resins were subsequently reacted with various secondary amines and partially neutralized with acetic acid to give thermally crosslinkable cationic resins. The resulting cationic resins were dissolved in suitable solvents and mixed with deionized water to form emulsions. The crosslinking properties, emulsion, and electrodeposition properties of these resins were studied in some detail. The electro-deposition yields of the emulsions prepared from aniline-modified epoxy resins were higher than those of other emulsions. The crosslinked films prepared from aniline-modified epoxy resins were also glossier than those prepared from commercial epoxy resins. High deposition yield and high glossiness were the characteristic properties of the aniline-modified epoxy resins. Thermal properties were not affected by aniline-modified epoxy resins.  相似文献   

5.
Epoxy resins were prepared from di-α-naphthol(4,4′-dihydroxy-1,1′-dinaphthyl) and di-β-naphthol(2,2′-dihydroxy-1,1′-dinaphthyl). The resins consisted mainly of the reaction product of 1 mole of dinaphthol with 2 moles of epichlorhydrin. They contained chlorine, however, and were correspondingly deficient in diepoxide functionality. The resins from di-α-naphthol were crystalline, had m.p. 200°C., and were not miscible with conventional curing agents. Di-β-naphthol gave resins with softening points in the range 50–70°C., which cured with diethylenetriamine or the anhydrides of dibasic acids, giving hard but brittle products. The brittleness was not removed by curing with plasticizing curing agents, such as tetrapropenyl succinic anhydride. The cured di-β-naphthol-based resins had thermal stabilities similar to analogous epoxy resins based on bisphenol A.  相似文献   

6.
Vinyl ester resins (VERs) are often described as a cross between unsaturated polyester resins and epoxy resins. VERs offer an upgrade to epoxy resins, and they tend to be selected when chemical and temperature resistance is required. This research was aimed at developing the synthesis of unsaturated ester resins (UERs), which are similar to VERs. UERs were synthesized by the addition of dihydrodicyclopentadienyl hydrogen maleate to the terminal epoxy groups in low‐molecular‐weight bisphenol A/epichlorohydrin epoxy resins. The effect of urethanization of UERs on the properties of the crosslinked polymer was also investigated. As crosslinking monomers, styrene and glycol dimethacrylates were used. The following properties of cured UERs were determined: the heat deflection temperature, alkali resistance, and the mechanical strength. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2627–2631, 2006  相似文献   

7.
This paper describes the work considering the potential for partially replacing phenol with organosolv lignin in phenol–formaldehyde resin used as an adhesive in the production of particleboard. Lignin-based resins were synthesised with organosolv lignin using various percentages of lignin replacement for phenol. The lignin was introduced to the resin in two different ways. The first method was the replacement of a certain percentage of phenol (5–40%) with lignin (as supplied) directly into resins. In the second method, lignin was modified by phenolation prior to resin manufacture. Different degrees of phenol substitution (20–30%) were investigated for the production of lignin-based resins. The physical properties of the formulated resins were measured and compared to commercial PF resin.  相似文献   

8.
含磷本质阻燃环氧树脂的研究进展   总被引:1,自引:1,他引:0  
贾修伟  楚红英  刘治国 《化工进展》2007,26(11):1546-1553
综述了含磷本质阻燃环氧树脂(包括含磷协同本质阻燃体系)的发展、现状和未来趋势。与添加型阻燃剂阻燃环氧树脂相比,通过含磷环氧化合物和/或含磷固化剂把磷元素嵌入环氧树脂结构中制得的含磷本质阻燃环氧树脂,具有阻燃效率高、阻燃持久、物理力学性能不受影响、燃烧过程中毒性腐蚀性挥发物质的生成量低等优势。利用协同阻燃效应,可以进一步提高阻燃性能。但是,含磷本质阻燃环氧树脂和含磷协同本质阻燃体系存在制备工艺复杂、生产成本较高等不足。  相似文献   

9.
Epoxy resins of different molecular weights were prepared from epichlorohydrin and 4,4′-sulfonyldiphenol (SDP) and from epicholorohydrin and bisphenol A (BA). They were cured at high temperatures with four different crosslinking agents, including aliphatic and aromatic amines. The thermal behaviour of these cured epoxy resins was studied. From the IPDT and IDT data it was observed that sulfone epoxy resins were thermally more stable than bisphenol A epoxy resins. The activation energies of thermal degradation of the resins were calculated and the implications of these results are discussed.  相似文献   

10.
It is not possible to improve the toughness of triallyl isocyanurate (TAIC) resins by applying the procedures useful for diallyl phthalate (DAP) resins as typical allyl resins. The results obtained are discussed in connection with the network structure of TAIC resin. Thus, the polymerization of TAIC would provide a homogeneous network accompanied by the incomplete occurrence of intermolecular crosslinking reactions caused by the rigidity of polymer chains, although DAP resins would consist of the microheterogeneous networks as the agglomerate of colloidal particles.  相似文献   

11.
Novolak resins fractionated using a liquid/liquid centrifugal fractionation/separation technique were characterized and contrasted to resins fractionated by conventional methods. The new fractionation method resulted in higher yields of resins with comparable or improved functional properties when used in i‐line sensitive (365 nm) photoresist formulations. By characterizing the isolateld resin and the lower molecular weight (Mw) fractions removed during fractionation, a better understanding of the structural differences associated with the fractionation processes could be determined. The potential for improving the fractionation/separation process and for obtaining higher yields and more consistent resists with the resins was identified.  相似文献   

12.
Two alkylresorcinol-based laminating resins, DFK-14R and FR-100, are compared in reactivity and structure with resorcinol- and phenol-based adhesive resins. The alkylresorcinols, derived from Estonian shale oil, replace costlier, less-reactive resorcinol in adhesives in the USSR. Differential scanning calorimetry quantitates the reactivity advantage. Infrared spectroscopy and proton nuclear magnetic resonance provide spectral patterns to distinguish the alkylresorcinol resins from the families of resorcinol-and phenol-based resins. Structural features are assigned for most of the spectral absorptions, with aid from 13carbon nuclear magnetic resonance spectra of the shale oil resins.  相似文献   

13.
Technical pure styrene monomer was cationically polymerized either alone or with α‐metylstyrene to prepare tackifying resins. Anhydrous aluminum chloride dispersed in toluene was used as the catalyst. The polymerization was optimized with emphasis on practical viewpoints, and incremental monomer addition method was used in all the syntheses. Certain parameters affected on the reaction and on the resin characteristics, i.e., starting reaction temperature, catalyst percent, monomer and comonomer concentration, and solvent type were investigated. Post‐heating of the resins was briefly studied as well. Number average molecular weight (Mn) and polydispersity (PDI) of the resins were determined by size‐exclusion chromatography. Changes of Mn and PDI, as well as the reaction rate and yield versus variation of the mentioned parameters, were basically investigated according to the mechanism of carbocationic polymerization. Finally, the structure of the synthesized resins was confirmed by IR and NMR spectroscopy. A graphical method was proposed to quantify comonomer composition of the copolymeric resins by using of the ratio of aromatic to aliphatic protons peak area from the corresponding NMR spectra. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2109–2119, 2001  相似文献   

14.
Summary Resins with carboxylic pendant groups were synthesized. The resins were characterized by elemental analyses and FT-IR spectroscopy, and the ability to bind copper (II) and uranium (VI) by batch method at different pH was studied. Uranium(VI) is adsorbed at pH 3 and pH 4 above 88%. The maximum capacity of load for uranium(VI) is higher than IRA-400, a commercial resin. Elution assays for Cu(II) and U(VI) from the loaded resins with sulfuric acid and sodium carbonate were also carried out.  相似文献   

15.
Oxazoline polyester resins were prepared by reaction of oxazoline diols from linseed acids and tris (hydroxymethyl) aminomethane with each of five dibasic acids (adipic, dimer, fumaric, itaconic and maleic). Certain resins were dissolved in isopropyl alcohol to give solutions infinitely water dilutable when the free carboxyl was neutralized with an amine. Film properties of resins cast on steel plates were investigated. Drying characteristics, hardness, color stability and solvent resistance of some of these films equaled or excelled those of a commercial soy alkyd resin, although their initial color was darker. The resins prepared from itaconic and maleic acids have potential value as water-solubilizable coating vehicles. Presented at the 151st ACS Meeting, Pittsburgh, March 1966. No. Utiliz. Res. Dev. Div., ARS, USDA.  相似文献   

16.
The alternating mechanism of network formation in the curing of epoxy resins from bisphenol A diglycidyl ether (BADGE) and amine curing agents does not offer any special opportunity for the formation of inhomogeneities caused by partial segregation or inhomogeneous crosslinking. Etched fracture surfaces of resins cured with 4,4′-diaminodiphenylmethane, hexamethylenediamine and hexahydrophthalic anhydride at various initial ratios of BADGE, studied by electron microscopy, reveal globular structures 20–40 nm in size. However, similar structures are observed with etched surfaces of amorphous polystyrene and poly(methyl methacrylate). The small-angle X-ray scattering curves for cured epoxy resins do not differ in principle from those of common amorphous polymers; swelling in a solvent of a lower electron density does not lead to an increase in scattering within the particle size range 10–102 nm. It is pointed out that the physical structure of simple cured epoxy resins does not essentially differ from that of common amorphous polymers. With more complicated systems, a more pronounced inhomogeneity might be caused by thermodynamic incompatibility or by non-alternating mechanisms of the curing reaction.  相似文献   

17.
Beom-Young Ryu  Todd Emrick 《Polymer》2009,50(3):767-1017
The diepoxide of bishydroxydeoxybenzoin, termed BEDB, was prepared and used as a diepoxide in adhesive formulations with various aromatic diamine cross-linkers. These novel epoxy resins were characterized and compared to the properties of bisphenol A (BPA)- and 3,3′,5,5′-tetrabromobisphenol A (TBBA)-based epoxies in terms of their thermal and mechanical properties. Cured formulations were characterized to determine glass transition temperatures by differential scanning calorimetry (DSC). The char residue, heat release capacity, dynamic mechanical properties, fracture toughness, and adhesion strength of the cured resins were investigated by thermogravimetric analysis (TGA), microscale combustion calorimetry, dynamic mechanical analysis (DMA), plain-strain fracture toughness tests, and lap shear tests. The BEDB-based resins exhibited significantly higher fracture toughness and adhesion strength compared to the BPA-epoxy resins, as well as low heat release properties (i.e., lower flammability) despite the absence of halogen.  相似文献   

18.
One method of reducing styrene emissions from vinyl ester (VE) and unsaturated polyester resins (UPE) is to replace some or all of the styrene with fatty acid-based monomers. Methacrylated fatty acid (MFA) monomers are ideal candidates because they are inexpensive, have low volatilities, and free-radically polymerize with vinyl ester. The viscosity of VE resins using these fatty acid monomers ranged from 700-2000 cP, which is considerably higher than that of VE/styrene resins (∼100 cP). In addition, the Tg of VE/MFA polymers were only on the order of 80 °C, which is significantly lower than that of VE/styrene polymers. Decreasing the length of the base fatty acid chains from 18 to 12 carbon atoms improved the Tg by 20 °C, while lowing the resin viscosity from ∼2500 to ∼1000 cP. Residual unsaturation sites on the fatty acid backbone decreased the cure rate of the resins thereby decreasing polymer properties. Ternary blends of VE, styrene, and fatty acid monomers also effectively improved the flexural, fracture, and thermo-mechanical properties and reduced the resin viscosity to acceptable levels, while using less than 15 wt% styrene, far less than commercial VE resins.  相似文献   

19.
胺化聚苯乙烯树脂的制备及吸附对硝基酚   总被引:1,自引:0,他引:1       下载免费PDF全文
孟启  舒斌斌  周峰  夏丰敏  孙小强 《化工进展》2015,34(6):1714-1719
以氯甲基化聚苯乙烯树脂(PS-Cl)和氯乙酰化聚苯乙烯树脂(PS-Acyl-Cl)为母体, 引入三乙烯四胺(TETA)制备两种胺化聚苯乙烯树脂PS-TETA与PS-Acyl-TETA。用红外光谱和表面孔径吸附仪对树脂进行表征, 并用于对硝基酚(PNP)的吸附研究。静态和动态吸附实验结果表明, 两种树脂对PNP的吸附过程都可以用准二级动力学方程来描述;液膜扩散为吸附PNP的主要控制步骤;吸附符合Freundlich等温方程, 为多分子层吸附;吸附为自发的放热过程, 属于以物理吸附为主的吸附过程;PS-TETA与PS-Acyl-TETA对PNP的饱和吸附量分别为157.87mg/mL、90.77mg/mL, 穿透体积为165BV、80BV, 动态脱附率为98.4% 、98.9%。  相似文献   

20.
王帅  钟宏  王仲南  张宝元  张骞 《应用化工》2010,39(5):747-750
树脂矿浆法(RIP)从溶液中提取与分离贵金属是目前的研究热点,其关键是制备高吸附容量和高吸附选择性的螯合树脂。讨论了选择性吸附贵金属离子的螯合树脂的分类方法、树脂结构与性能的关系、树脂与贵金属离子的配位机理,按配位原子分类综述了近10年来国内外螯合树脂的合成和吸附的研究进展,并展望了螯合树脂研究的发展方向。  相似文献   

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