In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate (TDI) in syntheticrubber track by ion chromatography (IC) coupled with an ultraviolet detector setting at 2...In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate (TDI) in syntheticrubber track by ion chromatography (IC) coupled with an ultraviolet detector setting at 212 nm. TDI can be hydrolyzed to toluene diamine (TDA) which can be separated by cation-exchange IC easily. The optimum IC separation was performed on an IonPac CS12A column (150 mm ×4.0 mm) using 20 mmol L^-1 sodium sulfate, 10 mmol L^-1 sulfuric acid and 10% acetonitrile as eluent. It was found that a higher signal response of TDA could be obtained under alkaline condition. A suppressor was used to change the acidic eluent into alkaline one. 0.8 mol L^-1 potassium hydroxide was chosen as the optimum regeneration eluent. With the added suppressor and regenerant, signal response was magnified by about 16 times and lower limit of detection (LOD, 0.13 μg L^-1) was obtained. Within-day relative standard deviation (R.S.D.) was less than 3.6%. The recoveries of TDI spiked in synthetic-rubber track samoles were 96.4-110.6%.展开更多
Controlled release of TDI and hence the cure characteristics of several blocked TDI with HTPB are reported. The reactions were followed through viscosity measurements as a function of time and temperature under the ca...Controlled release of TDI and hence the cure characteristics of several blocked TDI with HTPB are reported. The reactions were followed through viscosity measurements as a function of time and temperature under the catalytic influence of triethylamine. The effect of nature of substituents present on the end capping substrate, temperature, solvent, basicity of catalyst and kinetics thereon have been studied.展开更多
Cure characteristics of hydroxyl terminated polybutadiene (HTPB) prepolymer with avariety of blocked toluene diisocyanate (TDI) in the presence of triethylamine (TEA) andchloroacetic acid catalyst are reported. Phenol...Cure characteristics of hydroxyl terminated polybutadiene (HTPB) prepolymer with avariety of blocked toluene diisocyanate (TDI) in the presence of triethylamine (TEA) andchloroacetic acid catalyst are reported. Phenol, thiophenol, p-chloropheno1, p-nitrophenol,p-cresol, resorcinol, naphthols, caprolactam and butylated-hydroxytoluene were used as blockingagents. Viscosity measurements have been carried out using a mixture of HTPB and blocked TDIin cyclohexanone in the presence of the catalysts at 50℃ and 60℃ using Haake rotational vis-cometer. Viscosity measurements have also been carried out with 50% solids such as ammonium sulphate along with HTPB and TDI adduct.展开更多
Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated.The major characteristic of this procedure is that all the materials and reagents(silica,PEG,TDI,DBTDL,solvent)required for...Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated.The major characteristic of this procedure is that all the materials and reagents(silica,PEG,TDI,DBTDL,solvent)required for grafting were added simultaneously into the reaction vessel.TDI and DBTDL were used as coupling agent and catalyst,respectively. The products were characterized by FTIR,TGA,elemental analyses and TEM,giving evidence for successful grafting of PEG.Possible mechanism of this grafting was studied and two grafting processes were proposed.The process through which the grafting proceeds depends on the reaction temperature.Effect of molecular weight of PEG on grafting was also investigated.展开更多
针对目前精馏法处理TDI水解氯废水能耗高和能量利用率低的问题,以某化工厂TDI含氯废水为研究对象,建立自回热精馏技术提纯工艺。含有TDI及水解氯等重组分的原料液经进料泵送至产品塔进行连续精馏,从顶部分离出TDI产品,冷凝的物料进入回...针对目前精馏法处理TDI水解氯废水能耗高和能量利用率低的问题,以某化工厂TDI含氯废水为研究对象,建立自回热精馏技术提纯工艺。含有TDI及水解氯等重组分的原料液经进料泵送至产品塔进行连续精馏,从顶部分离出TDI产品,冷凝的物料进入回流罐,冷凝成液相也进入回流罐,再通过回流泵一部分回流入塔,另一部分采出,采出的TDI产品输送出界区。塔釜采出TDI和少量水解氯重组分,通过塔釜泵采出后输送出界区。采用Aspen Plus V11流程模拟软件对此流程进行模拟,确定了最优进料位置选第10块塔板,理论塔板数为15块塔板,回流比为1.0,塔顶基本没有水解氯存在,达到了要求的塔顶TDI含量≥99.90%、水解氯含量≤0.001 5%。基于自回热精馏降解TDI生产水解氯技术,仅需192 kW的电耗即能维持整个装置的正常运行,运行费用从614.4万元降为214.7万元,每年可降低65.06%的成本。展开更多
TDI(甲苯二异氰酸酯)交联改性PVA(聚乙烯醇)能明显提高PVA胶粘剂的耐水性和粘接性能。以PVA掺量、羧甲基纤维素(CMC)掺量、交联剂TDI掺量、催化剂-X掺量、交联温度和交联时间为试验因素,压缩剪切强度为考核指标,采用正交试验法优选出合...TDI(甲苯二异氰酸酯)交联改性PVA(聚乙烯醇)能明显提高PVA胶粘剂的耐水性和粘接性能。以PVA掺量、羧甲基纤维素(CMC)掺量、交联剂TDI掺量、催化剂-X掺量、交联温度和交联时间为试验因素,压缩剪切强度为考核指标,采用正交试验法优选出合成该改性PVA胶粘剂的最佳工艺条件。研究结果表明:当PVA为12 g/100 m L、CMC为3.2 g/100 m L、φ(TDI)=3%、φ(催化剂-X)=0.4%(均相对于胶粘剂体积而言)、交联温度为30℃和交联时间为45 min时,所合成的单组分TDI改性PVA胶粘剂具有良好的环保性、粘接性,可广泛应用于林产工业、纸品工业以及建筑行业等领域。展开更多
以甲苯二异氰酸酯(TDI)为交联剂,制备了TDI交联改性羧甲基纤维素(CMC)和聚乙烯醇(PVA)混合胶粘剂体系,并在交联反应完成后,用硼砂消乳增稠。采用正交试验法探讨了主要原材料配比、交联反应温度和交联反应时间等工艺条件对改性PVA胶粘剂...以甲苯二异氰酸酯(TDI)为交联剂,制备了TDI交联改性羧甲基纤维素(CMC)和聚乙烯醇(PVA)混合胶粘剂体系,并在交联反应完成后,用硼砂消乳增稠。采用正交试验法探讨了主要原材料配比、交联反应温度和交联反应时间等工艺条件对改性PVA胶粘剂性能的影响。研究结果表明:当PVA为12 g/100 m L、CMC为1.6 g/100 m L、TDI为4.00 m L/100 m L、硼砂为0.8 g/100 m L、交联反应温度为40℃和交联反应时间为90 min时,改性PVA胶粘剂具有良好的综合性能,其颜色稳定性及储存稳定性较佳,对木制品的粘接强度相对最好。展开更多
基金supported by the National Natural Science Foundation of China(No.20775070)Zhejiang Provincial Natural Science Foundation of China(No.Y507252).
文摘In the present work, a novel analytical method was proposed for the determination of toluene diisocyanate (TDI) in syntheticrubber track by ion chromatography (IC) coupled with an ultraviolet detector setting at 212 nm. TDI can be hydrolyzed to toluene diamine (TDA) which can be separated by cation-exchange IC easily. The optimum IC separation was performed on an IonPac CS12A column (150 mm ×4.0 mm) using 20 mmol L^-1 sodium sulfate, 10 mmol L^-1 sulfuric acid and 10% acetonitrile as eluent. It was found that a higher signal response of TDA could be obtained under alkaline condition. A suppressor was used to change the acidic eluent into alkaline one. 0.8 mol L^-1 potassium hydroxide was chosen as the optimum regeneration eluent. With the added suppressor and regenerant, signal response was magnified by about 16 times and lower limit of detection (LOD, 0.13 μg L^-1) was obtained. Within-day relative standard deviation (R.S.D.) was less than 3.6%. The recoveries of TDI spiked in synthetic-rubber track samoles were 96.4-110.6%.
文摘Controlled release of TDI and hence the cure characteristics of several blocked TDI with HTPB are reported. The reactions were followed through viscosity measurements as a function of time and temperature under the catalytic influence of triethylamine. The effect of nature of substituents present on the end capping substrate, temperature, solvent, basicity of catalyst and kinetics thereon have been studied.
文摘Cure characteristics of hydroxyl terminated polybutadiene (HTPB) prepolymer with avariety of blocked toluene diisocyanate (TDI) in the presence of triethylamine (TEA) andchloroacetic acid catalyst are reported. Phenol, thiophenol, p-chloropheno1, p-nitrophenol,p-cresol, resorcinol, naphthols, caprolactam and butylated-hydroxytoluene were used as blockingagents. Viscosity measurements have been carried out using a mixture of HTPB and blocked TDIin cyclohexanone in the presence of the catalysts at 50℃ and 60℃ using Haake rotational vis-cometer. Viscosity measurements have also been carried out with 50% solids such as ammonium sulphate along with HTPB and TDI adduct.
文摘Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated.The major characteristic of this procedure is that all the materials and reagents(silica,PEG,TDI,DBTDL,solvent)required for grafting were added simultaneously into the reaction vessel.TDI and DBTDL were used as coupling agent and catalyst,respectively. The products were characterized by FTIR,TGA,elemental analyses and TEM,giving evidence for successful grafting of PEG.Possible mechanism of this grafting was studied and two grafting processes were proposed.The process through which the grafting proceeds depends on the reaction temperature.Effect of molecular weight of PEG on grafting was also investigated.
文摘针对目前精馏法处理TDI水解氯废水能耗高和能量利用率低的问题,以某化工厂TDI含氯废水为研究对象,建立自回热精馏技术提纯工艺。含有TDI及水解氯等重组分的原料液经进料泵送至产品塔进行连续精馏,从顶部分离出TDI产品,冷凝的物料进入回流罐,冷凝成液相也进入回流罐,再通过回流泵一部分回流入塔,另一部分采出,采出的TDI产品输送出界区。塔釜采出TDI和少量水解氯重组分,通过塔釜泵采出后输送出界区。采用Aspen Plus V11流程模拟软件对此流程进行模拟,确定了最优进料位置选第10块塔板,理论塔板数为15块塔板,回流比为1.0,塔顶基本没有水解氯存在,达到了要求的塔顶TDI含量≥99.90%、水解氯含量≤0.001 5%。基于自回热精馏降解TDI生产水解氯技术,仅需192 kW的电耗即能维持整个装置的正常运行,运行费用从614.4万元降为214.7万元,每年可降低65.06%的成本。
文摘TDI(甲苯二异氰酸酯)交联改性PVA(聚乙烯醇)能明显提高PVA胶粘剂的耐水性和粘接性能。以PVA掺量、羧甲基纤维素(CMC)掺量、交联剂TDI掺量、催化剂-X掺量、交联温度和交联时间为试验因素,压缩剪切强度为考核指标,采用正交试验法优选出合成该改性PVA胶粘剂的最佳工艺条件。研究结果表明:当PVA为12 g/100 m L、CMC为3.2 g/100 m L、φ(TDI)=3%、φ(催化剂-X)=0.4%(均相对于胶粘剂体积而言)、交联温度为30℃和交联时间为45 min时,所合成的单组分TDI改性PVA胶粘剂具有良好的环保性、粘接性,可广泛应用于林产工业、纸品工业以及建筑行业等领域。
文摘以甲苯二异氰酸酯(TDI)为交联剂,制备了TDI交联改性羧甲基纤维素(CMC)和聚乙烯醇(PVA)混合胶粘剂体系,并在交联反应完成后,用硼砂消乳增稠。采用正交试验法探讨了主要原材料配比、交联反应温度和交联反应时间等工艺条件对改性PVA胶粘剂性能的影响。研究结果表明:当PVA为12 g/100 m L、CMC为1.6 g/100 m L、TDI为4.00 m L/100 m L、硼砂为0.8 g/100 m L、交联反应温度为40℃和交联反应时间为90 min时,改性PVA胶粘剂具有良好的综合性能,其颜色稳定性及储存稳定性较佳,对木制品的粘接强度相对最好。