Novel nitrogen‐containing epoxy resin. I. Synthetic kinetics

A novel nitrogen‐containing epoxy resin was synthesized by two steps: (1) condensation reaction between xyleneformaldehyde resin and phenol, to obtain thermoplastic xylenephenolformaldehyde (XPF) resin; and (2) addition reaction between XPF resin and triglycidyl isocryanurate (TGIC). The synthetic kinetics of XPF resin were intensively investigated by gel permeation chromatography (GPC). The results showed that XPF resin, with different molecular weights and low content of free phenol, could be obtained by changing the reaction conditions. The kinetics of reaction between XPF resin and TGIC was monitored by GPC and epoxy value titration. The results showed that the percentage conversion of TGIC was >85% within 60 min at 140°C and the epoxy value, about 0.3–0.4 mol/100 g, varied with the reaction conditions. This novel epoxy resin exhibited good stability of storage and could be used as a basic resin for making prepreg and laminate. The structures of XPF and XT resins were characterized by IR and ¹H‐NMR spectra. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96:723–731, 2005     

Design and synthesis of bio-based UV curable PU acrylate resin from itaconic acid for coating applications

UV curable PUA resin was successfully synthesized from polyol based on sustainable resource originated from itaconic acid (IA), isophorone diisocyanate (IPDI) and 2-hydroxyethyl methacrylate (HEMA). A polyol was synthesized by condensation reaction of IA with 16-hexanediol in the presence of p-Toluenesulfonic acid (pTSA). The synthesized PUA resin was characterized for its structural elucidation by using Fourier Transform Infrared Spectrophotometer (FTIR), ¹H and ¹³C NMR spectroscopy. The synthesized UV curable PUA resin was incorporated in varying concentrations in conventional PUA coating system. The effects of varying concentration of synthesized UV curable PUA resin on rheology, crystallinity, thermal and coating properties were evaluated. The rheological behavior of the resins were evaluated at variable stress and result showed decrease in viscosity of resin as concentration of synthesized UV curable PUA resin increases in conventional PUA resin. The cured coatings have been evaluated for glass transition temperature (T_g) and thermal behavior by differential scanning calorimeter and thermogravimetric analysis respectively. The degree of crystallinity of the coatings was determined from X-ray diffraction patterns using the PFM program. It was found that increase in the mass proportion of IA based PUA in coatings, the coating becomes more rigid and crystalline. The synthesized UV curable PUA coatings showed interesting mechanical, chemical, solvent and thermal properties as compared to the conventional PUA. Further, cured coatings were also evaluated for gel content and water absorption.     

Preparation of emulsion‐type thermotolerant sizing agent for carbon fiber and the interfacial properties of carbon fiber/epoxy resin composite

A modified resin was synthesized through the reaction between dodecylamine and tetraglycidyldiaminodiphenylmethane (TGDDM), which was used as the film former of sizing agent for carbon fiber (CF). The sizing agents were prepared through phase inversion emulsification method. Fourier transform infrared spectroscopy (FTIR) was utilized to analyze the modified resin. Particle sizes of the sizing agents were tested to evaluate their stabilities. Differential scanning calorimetry (DSC) results demonstrated that the glass transition temperature (T_g) of the modified TGDDM is much higher than the T_g of the cured epoxy resin E‐44. The influences of the sizing treatment on CF were investigated by abrasion resistance, fluffs, and stiffness tests. The maximum abrasion resistance increased by 172.8%, compared with the abrasion resistance of the desized CF. Interlaminar shear strength (ILSS) results of the CF/TGDDM composites indicated that the interfacial adhesion between CF and matrix resin was greatly improved after CF was sized. The maximum ILSS value could obtain a 29.16% improvement, compared with the ILSS of the desized CF composite. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41882.     

Tetrafunctional aliphatic epoxy I. Synthesis and characterization

A low viscosity tetrafunctional epoxy resin was synthesized by reacting amino-terminated polydimethylsiloxane with epichlorohydrin followed by dehydrohalogenation. The synthesized tetrafunctional aliphatic epoxy resin had an epoxy equivalent weight of 382, M_n of 1492, M_w of 2296, and a viscosity of 4.2 poise at 25°C. The chemical structure of the tetrafunctional aliphatic epoxy resin was studied by gel permeation chromatography (GPC), Fourier transform infrared spectra (FTIR), and ¹H-NMR spectra. Results showed the tetrafunctional aliphatic epoxy-blended aromatic epoxy resin possessed high impact strength and flexural strength. SEM photographs were investigated to study the compatibility of the blended epoxy system. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 51–58, 1998     

Novel Uncured Epoxy Resin/CaCO3 Nanocomposites

In this paper, we synthesized epoxy resin/CaCO₃ nanocomposites through in-situ and inclusion polymerization, and the nanoparticles were well dispersed in the resin matrix observed by SEM. The effects of the nanoparticles on the properties of epoxy resin are discussed.     

新型锂镁分离有机膦树脂的合成

以线性酚醛树脂为母体,其经溴甲基化、三乙氧基磷亲核取代及Arbuzov重排反应,合成一种新型有机膦树脂。该树脂经红外表征。通过Gauss软件对产物结构单元类似物进行频率计算,得到其理论计算红外图谱,与产物实测红外图谱进行比对,表明对酚醛树脂高分子骨架上官能团改造是成功的,合成了一种新型的有机膦树脂。     

Synthesis of liquefied corn barn-based epoxy resins and their thermodynamic properties

The liquefied corn barn-based epoxy resin (LCBER) was synthesized through the glycidyl etherification reaction from liquefied corn barn (LCB), which has groups of bound phenol, and epichlorohydrin under alkali conditions. The average molecular weights of LCB and LCBER in various liquefaction conditions were examined. The thermodynamic properties of thermosetting resin cured by polyamide-650 (PA-650) were evaluated. It was found that the macromolecular chain and epoxy function of the resins would be a dominant factor for crosslinking density and properties of the cured LCBER. The cured liquefied CB-based epoxy resin (LCBER-30) using the corresponding LCB at 30 min (LCB-30) as raw materials had much macromolecular exhibited higher glass-transition and decomposition temperatures at 5% weight loss (T_d), but worse shear strength in comparison with the other LCBER ones. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis of 3,13-diglycidyloxypropyloctaphenyl double-decker polyhedral oligomeric silsesquioxane and the thermal reaction properties with thermosetting phenol-formaldehyde resin

3,13-Diglycidyloxypropyloctaphenyl double-decker silsesquioxane (EP-DDSQ) was synthesized by process of alkaline hydrolysis condensation of phenyltrimethoxysilane and corner capping reaction of methyldichlorosilane, followed by hydrosilylation with allyl glycidyl ether, and the resultant structure was confirmed by fourier transform infrared spectrometer (FTIR) and nuclear magnetic resonance (NMR), respectively. The thermosetting phenol-formaldehyde (PF) resin was then modified by EP-DDSQ, and the reactivity of PF resin with EP-DDSQ and thermal pyrolysis of modified cured resin were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The surface morphologies of modified resins at high temperature were characterized with field emission scanning electron microscope (FESEM), and chemical structure of modified resins was analyzed through X-ray photoelectron spectrometer (XPS). The results showed that the appropriate addition of EP-DDSQ did not affect the curing temperature of the PF resin itself, but could improve the heat resistance of the system. When the amount of EP-DDSQ added was 10%, the initial degradation temperature of PF resin was increased by 49.31°C, and when the amount of EP-DDSQ added was 16%, the char yield of which was reached up to 61.39%, compared with that of pure PF resin (TGA_1,000°C of 57.62%) at Ar atmosphere. More importantly, the modified resin formed a regular and dense layer of SiC and SiO_x ceramic on the surface after ablation in the muffle furnace at 800°C air atmosphere, which is very important for ablative resistant materials.     

Synthesis and properties of vinyl siloxane modified cresol novolac epoxy for electronic encapsulation

Vinyl siloxane (VS) modified cresol novolac epoxy (CNE) and cresol novolac hardener (CNH) resins are synthesized and both components are capable of further crosslinking. The reaction kinetics for both components are studied so that they can crosslink simultaneously in a designed synthesis procedure. Through careful adjustment of a triphenylphosphine dosage, the glass‐transition temperature (T_g) of CNE/CNH resins can be effectively controlled. Phenomena characteristic of the existence of a diffusion‐controlled reaction are also observed. The relationships between the T_g and crosslinking density for the CNE/CNH resin are explicitly revealed through gel content and swell ratio experiments. CNE/CNH resins with a higher T_g have lower equilibrium moisture uptake because of the higher fraction of free volume. The coefficient of diffusion also shows a similar but less apparent trend. The incorporation of VS incurs a 35% reduction in the equilibrium moisture uptake and a 20% reduction in the coefficient of diffusion for the modified resin. The VS‐modified CNE/CNH resin possesses a lower Young's modulus and a higher strain at break than its unmodified counterpart does. This modified resin can help to alleviate the popcorning problems in integrated circuit packages, which results from hygrothermal stresses. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 652–661, 2001     

Preparation and characterization of weather resistant silicone/acrylic resin coatings

Preparation and characterization of weather resistant silicone/acrylic resin coatings were conducted. In order to prepare these coatings, a silicone/acrylic resin (KLD) was first prepared by an addition polymerization reaction of monomers, including n-butyl acrylate, methyl methacrylate, n-butyl methacrylate, and 3-methacryloxypropyltrimethoxysilane (MPTS). In the preparation of the silicone/acrylic resin, T_g of the acrylic copolymer was fixed at 40°C and the contents of MPTS were varied to be 10, 20, and 30 wt%. The weather resistant silicone/acrylic resin coatings were then prepared by blending the synthesized silicone/acrylic resin and TiO₂. The viscosity of the synthesized resin decreased with the content of MPTS, whereas the thermal stability at high temperature increased. The prepared coatings exhibited excellent adhesion to various substrates, and various physical properties of the coatings were satisfactory. The weatherability of the coatings was tested three ways: outdoor exposure test, Weather-Ometer (WOM), and QUV accelerated weatherability tester (QUV). The gloss retention, yellowness index difference, color difference, and lightness index difference were improved at high MPTS concentration. The coatings containing 30 wt% MPTS have especially good weather properties. Dept. of Chem. Eng., Yongin 449-728, Korea. Ansan 425-110, Korea.     

ION-EXCHANGE RESIN–CATALYZED SYNTHESIS OF POLYOXYMETHYLENE DIMETHYL ETHERS: A PRACTICAL AND ENVIRONMENTALLY FRIENDLY WAY TO DIESEL ADDITIVE

Polyoxymethylene dimethyl ethers (PODE_n) were synthesized via the reaction between dimethoxymethane (DMM) and trioxymethylene catalyzed by CT175, a macroporous strongly acidic cation-exchange resin. The influences of reaction conditions such as catalyst types, reaction temperature, time, pressure, catalyst dosage, and mass ratio of DMM to trioxymethylene were also investigated. Under the optimized conditions of m(dimethoxymethane):m(trioxymethylene) = 2.5:1, CT175 (7.5 wt.%), 90°C, 0.5 h, and 1.5 MPa, the conversion of trioxymethylene and the selectivity to PODE_3-8 was obtained as high as 89.0% and 64.2%, respectively. Moreover, the resin catalyst can be reused up to 20 times without obvious change in its activity. The 100% atom efficiency, green reaction process, mild reaction conditions, as well as easy workup make the protocol advantageous and acceptable.     

Thermal and mechanical properties of poly(urethane‐imide)/epoxy/silica hybrids

Improving properties of polyurethane (PU) elastomers have drawn much attention. To extend the properties of the modified PU composite, here a new method via the reaction of poly(urethane‐imide) diacid (PUI) and silane‐modified epoxy resin (diglycidyl ether of bisphenol A) was developed to prepare crosslinked poly (urethane‐ imide)/epoxy/silica (PUI/epoxy/SiO₂) hybrids with enhanced thermal stability. PUI was synthesized from the reaction of trimellitic anhydride with isocyanate‐terminated PU prepolymer, which was prepared from reaction of polytetramethylene ether glycol and 4,4′‐diphenylmethane diisocyanate. Thermal and mechanical properties of the PUI/epoxy/SiO₂ hybrids were investigated to study the effect of incorporating in situ SiO₂ from silane‐modified epoxy resin. All experimental data indicated that the properties of PUI/epoxy/SiO₂ hybrids, such as thermal stability, mechanical properties, were improved due to the existence of epoxy resin and SiO₂. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Facile synthesis of novel fluorescent phenol formaldehyde resin nanospheres for drug release

A highly-efficient nano-medical carrier system was constructed for drug release based on a facile synthesis, excellent fluorescence, and structure of phenol formaldehyde resin (PFR). The PFR was easily synthesized through a simple one-step hydrothermal reaction, reduction and etching process, and a silane coupling agent modification process. The multiple functionalized drug delivery system, defined as PFR-NH₂@DOX was constructed by loading Adriamycin (DOX) into PFR. Drug release results in vitro displayed a DOX content of 145 mg g⁻¹ prodrug nanosphere has excellent pH-triggered drug release (about 84.71%) within 72 h at pH 5 solution. The fluorescence recovery of PFR after DOX release indicates the potential application in fluorescence imaging and controlled drug release.     

联苯类液晶环氧树脂的合成研究

采用二步法合成液晶环氧树脂,首先合成含有刚性棒状介晶基元的联苯类环氧预聚体,将介晶基团通过共价键接入环氧树脂网络,再通过固化反应得到高度交联的液晶热固性树脂.探讨了固化剂及碱的用量、反应温度等对合成液晶的影响,利用IR与DSC等分析手段对合成的单官能团液晶环氧化合物（SCEP）和液晶环氧树脂进行结构表征,结果表明合成的物质为低分子液晶环氧化合物.     

Preparation and characterization of POSS‐SiO2/cyanate ester composites with high performance

In this article, a hybrid filler based on polyhedral oligomeric silsesquioxane and silica, coded as POSS‐SiO₂, has been successfully synthesized. The structure of POSS‐SiO₂ was studied by Fourier‐transform infrared spectra, X‐ray diffraction, and scanning electron microscopy. Then the POSS‐SiO₂ was compounded with dicyclopentadiene bisphenol dicyanate ester (DCPDCE) resin to prepare composites. The effects of POSS‐SiO₂ on the curing reaction, mechanical, thermal, dielectric and tribological properties of DCPDCE resin were investigated systematically. Results of differential scanning calorimetry show that the addition of POSS‐SiO₂ can facilitate the curing reaction of DCPDCE and decrease the curing temperature of DCPDCE. Compared with pure DCPDCE resin, the impact and flexural strengths of the composites materials are improved markedly with up to 72 and 52% increasing magnitude, respectively. Meanwhile, the POSS‐SiO₂/DCPDCE systems exhibit lower dielectric constant and loss than pure DCPDCE resin over the testing frequency from 10 to 60 MHz. In addition, the thermal stability and tribological properties of POSS‐SiO₂/DCPDCE composites are also superior to that of pure DCPDCE resin. POLYM. COMPOS., 36:1840–1848, 2015. © 2014 Society of Plastics Engineers     

双马来酰亚胺增韧研究 Ⅰ.改性双马来酰亚胺树脂的制备与性能

本文合成和分析了双马来酰亚胺和邻-二烯丙基双酚A,并从它们制备了双马来酰亚胺改性树脂;用FT-IR和DSC技术检测了树脂的固化反应;最后对树脂的性能进行了表征.     

Chemically decomposable imine-based thermoset using oxidized sugar

Increasing environmental concerns have driven the pursuit of sustainable alternatives to petrochemical-based plastics in polymer chemistry. In this study, we demonstrated a method by which sugar, the most chemically produced biomass, can be used as a thermosetting resin. The sucrose was successfully oxidized, synthesized, and then incorporated into a resin. Sodium periodate (NaIO₄) was used to convert sucrose into chemical raw materials. The resulting polymer, prepared via the imine reaction, exhibited a glass transition temperature T_g of 96°C, as determined by differential scanning calorimetry. Additionally, the thermosetting resin exhibited a tensile strength of 7 MPa, a modulus of 515 MPa, and a T_g of 100°C. We obtained reaction rate constants of 0.7 × 10⁻³ h⁻¹ and 3.2 × 10⁻¹ h⁻¹ using THF and citric acid solutions, respectively. Furthermore, we reused the resin from the decomposed organic matter and confirmed that the resynthesized overall, our findings suggest the potential for green recycling by converting commonly used sugars into nature-derived raw materials, leading to the development of eco-friendly polymer synthesis.     

Synthesis and separation properties for Cu(II)‐Ni(II) of macroporous crosslinked polystyrene‐supported triethylenetetramine resin using Cu(II) as template

A new method for preparing a novel macroporous chelating resin that has good adsorption capability for Cu(II) and high selectivity for it with the coexistence of Ni(II) was introduced in this article. First, the aminated resin (PS‐TETA) was synthesized by the reaction of crosslinked macroporous chloromethylated polystyrene with triethylenetetramine. Subsequently, PS‐TETA was coordinated with Cu(II) and then PS‐TETA‐Cu was obtained. After the crosslinking reaction of PS‐TETA‐Cu with epoxy chloropropane, the adsorbed Cu(II) was removed by chlorhydric acid, and then the target resin‐Cu(II) template triethylenetetramine crosslinked polystyrene resin was obtained. The selectively sorption tests for Cu(II) showed that the sorption capacity was as high as 1.6 mmol/g and the selectivity coefficient α_{Cu(II)/Ni(II)} could reach to 9.06 with the coexistence of Ni(II). SEM and nitrogen adsorption at 77 K methods were used to characterize the porous structure of the resin. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 963–967, 2007     

Preparation of copoly(vinyl alcohol–styrenesulfonic acid) resin and its catalytic activity on hydrolysis of carbohydrates. IV. Hydrolysis of dextrin in mixtures of organic solvents with water

The reaction rates of dextrin hydrolysis in the presence of copoly(vinyl alcohol–styrenesulfonic acid) resin in mixtures of dimethyl sulfoxide and dioxane with water were measured and compared with those in the presence of Amberlite 120B. In the case of Amberlite 120B the second-order rate constant, κ₂, of the reaction decreased continuously with increasing vol % of the organic solvents, whereas in the case of the copolymer resin it passed a minimum and increased again at the higher vol % range. The influence of blocking of the hydroxyl groups in the copolymer resin by formalization on the catalysis was investigated. The increase in κ₂ in the higher vol % range of the organic solvent was suppressed with the blocking, and the interactions between hydroxyl groups in the substrate and the copolymer resin was confirmed to play an important role for the increase in the κ₂ in the higher vol % range of the organic solvents. Temperature dependence of κ₂ was also examined, and the increase in κ₂ in the higher vol % range of the organic solvents was found to be due to pronounced decreases in enthalpy of activation, suggesting that the increase might be resulted from the enhancement of interactions between the substrate and the catalytic copolymer resin.     

煤沥青基吸水树脂的制备与性能

以煤沥青为原料、空气为氧化剂、碱性水溶液为介质,考察了液固比、固碱比及反应时间等对煤沥青氧化率的影响。在此基础上,本文将煤沥青氧化液体产物（LP）直接与丙烯酸（AA）通过溶液聚合法制备出高吸水树脂。通过单因素与正交设计实验确定各因素对树脂吸水性能的影响,进而确定出合成树脂的最佳反应条件。同时,对合成树脂进行了结构表征与反应机理分析。结果表明,LP同丙烯酸、过硫酸铵和N-N′-亚甲基双丙烯酰胺在温度为75℃、时间为30min的最佳反应条件下合成的树脂具有最大吸水值,而红外吸收光谱证实合成的树脂含有LP中芳香组分的芳环特征吸收峰。其中,在去离子水与0.9%（质量分数）NaCl水溶液中最大吸水倍率分别为613.3g/g与42.2g/g,而合成树脂的机理是LP中的苯多酸与AA和N,N′-亚甲基双丙烯酰胺通过酯基联结而成。该研究为高效利用煤沥青探索出一条可供选择的新途径。