端烯丙基超支化聚醚多元醇的制备及表征

以三羟乙基异氰脲酸酯(THEIC)为起始剂、自制双金属氰化络合物(DMC)为催化剂、环氧丙烷(PO)与缩水甘油开环聚合制备端羟基超支化聚醚多元醇(HTHP);然后与烯丙基缩水甘油醚(AGE)、PO反应制备端烯丙基超支化聚醚多元醇。讨论了HTHP与PO的质量比(RHTHP/PO)、AGE与PO的质量比(RAGE/PO)、DMC催化剂加入量对聚合反应的影响,采用红外谱图和核磁谱图对产物进行表征。结果表明,增加RHTHP/PO有利于缩短诱导期和聚合反应时间,同时可增加收率;当RAGE/PO为1∶20时,收率最高;DMC催化剂最佳质量分数为200×10-6;表征证实了端羟基超支化聚醚多元醇中成功引入了双键,合成了端烯丙基超支化聚醚多元醇。     

蓖麻油基聚醚多元醇的制备及其表征

以双金属氰化物(DMC)为催化剂、蓖麻油为起始剂制备了新型蓖麻油基聚醚多元醇.采用傅立叶变换红外(FTIR)、核磁共振(1H-NMR)、凝胶色谱(GPc)及热失重(TG)等分析手段对合成产物的结构和热稳定性进行表征.结果表明,蓖麻油基聚醚多元醇结构中既含有蓖麻油的酯基和双键,又含有聚醚的烷基醚基团;本实验的蓖麻油基聚醚多元醇相对分子质量分布随相对分子质量的增大而变窄;与普通聚醚多元醇相比具有更高的热稳定性.     

微波液化木材及聚醚多元醇的制备

以醇解的聚酯(PET)饮料瓶为液化剂,甘油作辅助液化剂,微波辅助加热,用2.5%H2SO4催化液化木材。分别讨论了微波功率、液固比/反应时间和温度对液化率的影响。结果表明,在微波功率500 W,反应时间15 m in,温度150℃,液固比为4的条件下,木材液化率99.16%。以此液化物为起始剂,选用双金属氰化物MMC催化环氧丙烷开环聚合,通过改变环氧丙烷的用量制备了不同聚醚多元醇,并采用傅里叶变换红外(FT-IR)、凝胶色谱(GPC)及热示差扫描(DSC)等分析手段对起始剂和不同聚醚多元醇的结构、分子质量分布和耐热性进行了对比表征。研究表明聚醚多元醇的羟值、酸值、黏度随环氧丙烷用量增加减小,分子质量分布随之变窄,热稳定性下降。     

粗聚醚多元醇精制工艺的研究

以ZS 2 80 1碱性粗聚醚多元醇为原料 ,采用吸附法 ,研究了聚醚多元醇中杂质钾、钠离子的脱除精制工艺。结果表明 ,成品聚醚多元醇中的钾、钠离子总量可控制在 10× 10 - 6 以下 ,可以满足软质PU泡沫塑料的应用要求。选用的吸附剂具有价廉、夹带成品聚醚多元醇少等优点。     

国内外聚醚多元醇开发进展

评述了聚醚多元醇的生产技术与产品开发进展,以及世界和中国的聚醚多元醇市场分析,并提出了发展建议。     

聚醚多元醇的研究进展

聚醚多元醇是生产聚氨酯原料之一,本文从聚醚多元醇合成工艺入手,重点从催化剂角度阐述了聚醚多元醇的合成,并对今后的发展提出建议.     

聚氨酯用聚醚多元醇的改性

综述了各种聚氨酯用改性聚醚多元醇 ,包括聚合物多元醇、聚脲多元醇、聚合多元醇和不饱和聚酯多元醇等 ,重点介绍了应用比较广泛的聚合物多元醇和聚脲多元醇。     

一种新型软泡聚醚多元醇的研制

在碱性催化剂作用下,甘油与环氧丙烷和环氧乙烷进行混聚成粗聚醚多元醇,经中和、干燥、过滤得到软泡聚醚多元醇。该聚醚多元醇的质量指标为羟值54～58mg/g,粘度400～600mPa.s,酸值0.05mg/g,pH值5～7。     

聚醚多元醇工业现状分析

介绍了聚醚多元醇的分类用途及其生产原料,分析了国内外聚醚多元醇的生产概况及聚醚多元醇工业面临的挑战。     

Polyurethane wood adhesive from palm oil-based polyester polyol

Polyurethane (PU) adhesives for wood bonding were prepared from palm oil-based polyester polyol in a solventless condition that reduces the risk of volatile organic compounds to human health and the environment. The polyester polyol was synthesized from epoxidized palm olein prior to reacting with polymeric 4,4′-methylene diphenyl diisocyanate (pMDI) and toluene 2,4-diisocyanate (TDI) to produce wood-bonding PU adhesives. The effect of glycerol cross-linker, dibutyltin dilaurate catalyst and NCO/OH ratio on lap shear strength and pot life of the PU adhesives were studied. The green strength of the PU adhesives was achieved on day 4 for TDI-based adhesives and day 5 for pMDI-based adhesives. The newly formulated PU adhesives have superior chemical resistance in cold water, hot water, acidic medium and alkaline medium by only showing light deterioration (2–8%) in lap shear strength. The PU adhesives prepared from pMDI exhibited higher lap shear strength and thermal stability as compared to adhesives prepared from TDI adduct. Both adhesives have improved mechanical performance (two folds higher in lap shear strength) as compared to commercial wood bonding adhesives.     

天然雌激素色谱-质谱检测方法研究进展

天然雌激素在生物体中起着重要的作用,各种样品中天然雌激素的检测具有一定的难度,液-液萃取、固相萃取及固相微萃取等样品前处理方法结合气相色谱-质谱及液相色谱-质谱检测成为天然雌激素检测的重要手段,综述了天然雌激素的检测方法研究进展情况。     

改性淀粉木材胶粘剂的制备及表征

以过硫酸铵为引发剂,以玉米淀粉、乙酸乙烯酯和丙烯酸丁酯为原料,制备改性淀粉木材胶粘剂,在单因素实验的基础上,进行L_(16)(4~5)正交实验,优化改性淀粉木材胶黏剂的制备条件。结果表明,最佳制备工艺参数为:引发剂浓度11 mmol/L,单体与淀粉质量比为1.0,反应温度70℃,单体乙酸乙烯酯和丙烯酸丁酯的质量比为3∶2,反应时间3 h。在此条件下,接枝率达91.3%,制备的改性淀粉木材胶粘剂性质较佳,各项指标均达到聚乙酸乙烯酯木材胶粘剂化工行业标准HG/T 2727—2010。     

新型高活性聚醚多元醇的制备及应用

详细介绍了用三(五氟苯基)硼烷为代表的新型Lewis酸催化剂制备高活性聚醚多元醇的工艺,并介绍了该高活性聚醚多元醇在聚氨酯(PU)泡沫及弹性体中的应用情况,指出用该新型聚醚多元醇制备的PU树脂具有优异的固化特性、力学性能、耐水性和湿热稳定性。     

桐木胶的研制

主要探讨了如何解决用于桐木拼板中的胶粘剂的显色、耐水、耐低温的问题。     

不同含量配比制备聚氨酯泡沫及其性能研究

采用一步法以异佛尔酮二异氰酸酯和聚醚多元醇为原料,选用A～D4种配比制备了聚氨酯泡沫材料,通过红外光谱仪、扫描电子显微镜、差示扫描量热仪、热重分析仪和噪声振动测试系统等对聚氨酯泡沫的泡孔结构、热稳定性及吸音隔音性能进行了测试.结果表明,聚醚多元醇的用量对聚氨酯泡沫成分未造成差异,聚氨酯泡沫中出现闭孔、半闭孔、开孔并存现...     

Synthesis and properties of polyurethane wood adhesives derived from crude glycerol-based polyols

Crude glycerol, a waste stream of the biodiesel production process, is low-cost renewable feedstock for the production of chemicals and polymers. In this study, polyurethane (PU) adhesives were synthesized from crude glycerol-based polyols (CG-based polyols) for wood bonding applications. Effects of different variables, including hydroxyl values of CG-based polyols, chain extenders, and the molar ratio of NCO/OH on the properties of PU adhesives were investigated. The chemical structures of PU adhesives were characterized, and their thermal, mechanical, and chemical resistance properties were evaluated. The experimental results indicated that an increase of the NCO/OH molar ratio (1.3) substantially improved bonding strength by up to 38 MPa. Higher thermal stability and stronger chemical resistance to hot and cold water and to alkali and acid solutions were observed comparing to vegetable oil-based adhesives. However, the effect of the hydroxyl value of polyols on bonding strength was not significant. Additionally, bond strength of crude glycerol-based PU adhesives was comparable to that of some commercial PU wood adhesives. All these properties demonstrated the potential of CG for PU wood adhesive applications, particularly for fast-curing uses.     

木粉基吸附剂的制备及性能研究

制备并研究了木粉基重金属离子吸附剂对金属离子的吸附性能.结果表明,吸附剂对Pb2 、AS 、Cu2 、Mn2 4种离子的饱和吸附容量分别达89.46、73.92、22.25 mg/g和21.8 mg/g,是木粉接枝共聚前吸附容量的4～10倍.吸附剂对所研究的金属离子的吸附特征可用Freundlich方程近似描述.找到了Pb2 、Ag 、Cu2 、Mn2 适宜吸附的pH范围,再生实验表明吸附剂经3次再生之后仍保持较高的吸附容量.     

支链聚醚原油破乳剂的合成与表征

以聚氧乙烯聚氧丙烯环氧基醚和聚氧乙烯聚氧丙烯甲基醚为支链,聚硅氧烷为主链,在异丙醇溶剂下,以氯铂酸为催化剂,通过硅氢加成反应,合成出聚醚聚硅氧烷类原油破乳剂。得到较佳的合成条件为:n(环氧醚)∶n(甲基醚)=1∶1,n(硅氢键)∶n(双键)=1∶1.15,反应温度105℃,反应时间5 h,催化剂用量30μg/g(相对于反应物总质量)和溶剂用量40%(以原料总质量计),在该条件下转化率达到92.62%,并通过FTIR和1HNMR对产物的分子结构进行了表征,谱图分析证明合成了预期产物。表面张力仪测定了其临界胶束质量浓度为0.7 g/L,最低表面张力24.2 mN/m。该破乳剂在破乳温度70℃,用量为100 mg/L条件下,对延长石油永平原油的脱水率达到88.42%,具有较好的破乳性能。     

Preparation,characterization and properties of an organic siloxane-modified cassava starch-based wood adhesive

A new method of preparing a cassava starch-based wood adhesive with high performance using hydrogen peroxide, acrylamide, butyl acrylate (BA), and an organic siloxane as an oxidant, a hard co-monomer, a soft co-monomer, and crosslinking agent, respectively, is proposed. The effects of various parameters on the shear strength, the water resistance, and the viscosity of the adhesive were investigated. The results showed that the shear adhesive strength in dry state and wet state of cassava starch-based adhesive could reach 6.11 MPa and 3.05 MPa, respectively. The organic siloxane, when added, could reduce the content of the hydroxyl on the starch molecule, and promote the crosslinking of the starch molecules, improving the bonding strength and water resistance.