双酚A戊二醛酚醛树脂的合成及表征

以双酚A(BPA)、戊二醛(GA)为原料,正丁醇为溶剂,在碱性条件下合成了双酚A戊二醛酚醛树脂(BPA-GA酚醛树脂)。通过红外光谱仪(FT-IR)、核磁共振氢谱(¹H-NMR)和元素分析对产物进行了结构表征,并分别探讨了醛酚比、催化剂用量、溶剂用量、反应温度和反应时间这五个因素对BPA-GA酚醛树脂固体含量的影响。研究结果表明:利用响应面法优化BPA-GA酚醛树脂的最佳工艺条件,即醛酚比为0.7∶1,催化剂用量为0.15 g,溶剂用量为35 mL,反应温度为95℃,反应时间为6 h。     

双酚A型线性酚醛树脂的合成

本文报导了一种新型耐热性双酚Ａ线性酚醛环氧树脂固化剂的合成,对该固化剂合成过程中的影响因素作了研究,取得了较佳的合成工艺条件,并对其环氧树脂固化物的耐热性能作了初步研究。     

响应面法优化过氧化氢强化水力空化去除双酚A

利用响应面法(RSM)对过氧化氢强化水力空化(HC/H_2O_2)去除双酚A(BPA)工艺进行设计,建立拟合二次多项式回归模型。结果表明,多项式模型的3个因素对BPA去除效果的影响顺序:入口压力过氧化氢浓度空化时间。HC/H_2O_2技术去除BPA的优化条件:入口压力为0.31 MPa,过氧化氢质量浓度为10.31 mg/L,空化时间为138.81 min。在此条件下BPA去除率的预测值为36.36%,根据实际情况修正优化参数与预测值仅相差0.12%,说明回归方程拟合性较好,模型得到的工艺参数可靠。     

双酚A型含氮酚醛树脂的合成及应用研究

以双酚A、甲醛和三聚氰胺等为原料合成了含氮酚醛树脂,并对环氧树脂的阻燃改性,制得了电性能良好且阻燃性优异的阻燃环氧树脂。     

线型双酚A酚醛树脂的合成

对线型双酚A酚醛树脂的合成工艺及催化剂浓度、种类、反应时间、醛酚比等影响因素进行了研究。结果表明,随着反应物醛酚比的增大,产物中残留的BPA量呈下降趋势,软化点先上升后下降,在1.2左右出现峰值;随反应时间延长,产物的软化点升高,分子质量增大,残留BPA量减少,分子质量分散性增加;催化剂用量增大,分子质量增大,软化点增高,残留BPA含量降低。合理的催化剂用量为m(BPA)∶m(催化剂)=100∶20。以合成的BPAN代替双氰胺(D ICY)作环氧树脂EB454A80的固化剂,在相同的固化工艺条件下,固化物的Tg提高近12℃。     

双酚A改性甲价酚醛树脂的合成和表征

利用双酚A、苯酚、甲醛水溶液为原料，在KOH的催化下，合成了一种含有羟甲基的双酚A改性甲阶酚醛树脂，研究了反应温度、反应物配比、催化剂用量、反应时间对合成的影响，并用红外光谱分析了产品的结构。结果表明，在反应温度为80℃，反应时间为3h条件下，各反应物物质的量比的适宜范围：n(甲醛)：n(苯酚)为（3.0-3.5）:1;n(氢氧化钾)：n(苯酚)为（0.085-0.15）:1;n(双酚A)：n(苯酚)为（0.1-0.35）:1。     

环氧树脂新型固化剂—双酚A线性酚醛树脂的合成反应研究

本文介绍了一种环氧树脂新型固化剂－双酚Ａ线性酚醛树脂的合成方法,探讨了醛酚比、反应时间、反应温度、催化剂种类及加入量对产物软化点、分子量、残留ＢＰＡ含量的影响。     

双酚A改性甲阶酚醛树脂的合成和表征

利用双酚A、苯酚、甲醛水溶液为原料,在KOH的催化下,合成了一种含有羟甲基的双酚A改性甲阶酚醛树脂,研究了反应温度、反应物配比、催化剂用量、反应时间对合成的影响,并用红外光谱分析了产品的结构。结果表明,在反应温度为80℃,反应时间为3 h条件下,各反应物物质的量比的适宜范围:n(甲醛):n(苯酚)为(3.0～3.5):1,n(氢氧化钾):n(苯酚)为(0.085～0.15):1;n(双酚A):n(苯酚)为(0.1～0.35):1。     

合成双酚A副产物的研究

本文详细介绍了压制Ⅰ类胶合板的混酚甲醛树脂的生产工艺,对配方和工艺条件进行了讨论,确定了最佳工艺,并介绍了中试、工业生产和工业应用情况。     

“双酚A下脚”酚醛树脂胶在纤维板生产中的应用

在合成双酚A时 ,会产生一些下脚废料 ,而这些废料通过一定的反应可以生产成酚醛树脂 ,替代用苯酚生产的纯酚醛树脂 ,用于纤维板的生产。     

双酚A-多聚甲醛酚醛树脂的合成与表征

采用双酚A(BPA)和多聚甲醛(PA)为原料,少量水为多聚甲醛解聚促进剂,在酸性条件下合成了高分子量热塑性酚醛树脂,并对产物的结构、元素、相对分子量、热稳定性和荧光性等进行测定.以BPA-PA酚醛树脂固含率为衡量指标,探讨了不同因素对合成的影响规律.通过响应面设计对树脂合成工艺进行优化,确定了较佳合成工艺条件为PA用量...     

双酚F/间苯二酚共聚型环氧树脂的合成

为提高双酚F环氧树脂的综合性能,以双酚F、间苯二酚与环氧氯丙烷反应制得双酚F／间苯二酚共聚型环氧树脂。研究了催化剂用量、反应温度、反应时间以及闭环时的加碱速度等因素对产物性能的影响,并对产物进行了表征。结果显示,其最佳合成工艺条件是:间苯二酚与双酚F质量比为20:80,催化剂摩尔分数为2．0％．醚化温度为80℃,醚化时间为5 h,闭环时加碱速度为0．4g/min。     

Response surface optimization for improving the processing behavior of melamine formaldehyde impregnation resins

Melamine-formaldehyde resins are widely used for decorative paper impregnation. Resin properties relevant for impregnation are mainly determined already at the stage of resin synthesis by the applied reaction conditions. Thus, understanding the relationship between reaction conditions and technological properties is important. Response surface methodology based on orthogonal parameter level variations is the most suitable tool to identify and quantify factor effects and deduce causal correlation patterns. Here, two major process factors of MF resin synthesis were systematically varied using such a statistical experimental design. To arrive at resins having a broad range of technological properties, initial pH and M:F ratio were varied in a wide range (pH: 7.9–12.1; M:F ratio: 1:1.5–1:4.5). The impregnation behavior of the resins was modeled using viscosity, penetration rate and residual curing capacity as technological responses. Based on the response surface models, nonlinear and synergistic action of process factors was quantified and a suitable process window for preparing resins with favorable impregnation performance was defined. It was found that low M:F ratios (~1:2–1:2.5) and comparatively high starting pHs (~pH 11) yield impregnation resins with rapid impregnation behavior and good residual curing capacity.     

磺甲基酚醛树脂在水中的分散特性

考察了SPF(磺甲基酚醛树脂)在去离子水、氯化钠溶液和不同pH溶液中的分散特性,并对分散体系浊度变化规律、分子聚集体尺度和Zeta电位进行了测定。研究结果表明:SPF在去离子水中具有良好的分散稳定性,分子聚集体粒径较小;在低氯化钠浓度下,体系稳定性较好,浊度不随时间增加;盐浓度增加后,Zeta电位绝对值减小,体系失去分散稳定性,浊度随时间显著增加;当pH大于1.95时,体系分散稳定性较好,随着pH的降低,Zeta电位绝对值和体系分散稳定性降低,而浊度随着时间增加。     

低甲醛含量脲醛树脂粘合剂的合成方法研究

提出了降低脲醛树脂(UF)粘合剂中游离甲醛含量的措施以及改性的方法,摸索出了实用且简单可行的合成方法。根据此合成方法生产的产品具有黏度适宜、反应易控制、甲醛含量低、成本低等优点。树脂的甲醛含量达到国家室内板用粘合剂游离甲醛含量标准。     

Regeneration and utilization of waste phenolic formaldehyde resin: A performance investigation

Recycled thermosetting phenolic formaldehyde (RPF) resins were pulverized to micron-sized powders and successfully reused as an effective component by reactive-injecting with neat phenolic formaldehyde (PF) and/or trioxymethylene (TOX) to prepare regenerated phenolic formaldehyde (i.e., and ). Tensile strength (σ_f), impact strength (I_s), and density (ρ) of and specimens were reduced as RPF concentrations or average particle sizes increased. It is worth emphasizing that σ_f, I_s, and ρ of each reaction-injected series having a fixed RPF concentration and average particle size improved to a maximum value, as TOX concentrations reached a corresponding optimal value. This is the first investigation to report that σ_f and I_s of proper regenerated PF/RPF/TOX specimens using ≦20 wt % RPF waste were ≥ 95% of those of the virgin reaction-injected PF. Possible reasons accounting for these improved mechanical properties were proposed based on results from their Fourier transform infrared analysis (FTIR). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47445.     

纳米二氧化硅改性磺甲基酚醛树脂的合成与评价

本文从一种磺甲基酚醛树脂的合成配方入手,通过不断试验调节最终确定磺甲基酚醛树脂的合成路线,并在合成过程中加入一种纳米粒子,并对这种合成的磺甲基酚醛树脂按照SY-T 5094-95石油行业标准进行评价[4]。在试验过程中得出,在合成酚醛树脂过程中pH在2左右,(n)P∶(n)F=1∶1.2,在磺化过程中分别采用一步和分步磺化的方法,得出温度应该控制在105℃,pH至少应该控制在10以上。     

Lignin-modified phenolic resin: synthesis optimization,adhesive strength,and thermal stability

Lignin-modified phenolic resin has been prepared by replacing phenol with lignin at different weight percentages. The resin synthesis was optimized by varying the molar ratio of phenol to formaldehyde, the concentration of sodium hydroxide, and the reaction time by measuring parameters such as the gelation time, flow time, solids content, pH, and specific gravity. The thermal stability of lignin-modified phenolic resin was studied by DSC, TGA, and isothermal analysis, and it was found that lignin-modified phenolic resin is thermally more stable than pure phenolic resin. The adhesive strength of lignin-modified phenolic resin was determined by the lap-shear method, which showed that the lignin-modified resin retains 78% of the adhesive strength for wood-wood systems and 86% of the adhesive strength for Al-Al systems.     

A 13C-NMR analysis method for phenol–formaldehyde resin strength and formaldehyde emission

A method based on the use of ¹³C-NMR relative peak intensity ratios for different characteristic chemical groups, known or supposed to contribute to phenol–formaldehyde (PF) resin strength and formaldehyde emission is presented. The method relates results obtained by ¹³C-NMR analysis of liquid PF resins with the strength and formaldehyde emission in the resin-hardened state. Correlation of differnt peak ratio with experimental results allows the proposal of equations relating the sum of different ¹³C-NMR peak ratios with the two mentioned physical properties of the same resins in their hardened state. The equations presented appear to have some applied value in predicting physical properties of hardened industrial-type PF resins from a single ¹³C-NMR spectrum of the original liquid resin, as well as to render easier comparison between different PF resin formulations. © 1995 John Wiley & Sons, Inc.     

特种氢化双酚A型环氧树脂合成研究

氢化双酚A和环氧氯丙烷在催化剂作用下开环反应生成了氯醇醚,而后加碱进行闭环反应,制备了低分子质量氢化双酚A型环氧树脂,再将其进一步与氢化双酚A等进行加聚反应,得到高分子质量环氧树脂。通过对产物的环氧值、力学性能和电性能的测试,研究了环氧氯丙烷用量、碱用量、环化反应温度、时间、溶剂及催化剂对合成反应的影响。结果表明,最佳反应条件为:环氧氯丙烷与醇羟基的物质的量比为3.0~3.5∶1,n(NaOH)∶n(醇羟基)=1∶1.1~1.2,环化反应温度25~30℃、时间4 h,甲苯为溶剂,催化剂为自制EH-10。所得氢化双酚A环氧树脂质量稳定,可替代进口。