【作者】 谢艳霞；

【导师】 宗志敏；

【作者基本信息】 中国矿业大学 ， 化学工艺， 2013， 博士

【摘要】 近年来，随着国内钢铁、水泥、焦炭等行业的快速发展，对于输送高温物料的耐热输送带的需求日益突出，中国橡胶工业协会管带分会把耐高温输送带的开发列入行业十二五发展规划。本文目的在于研制符合GB/T20021-2005的T4/175℃新型耐热输送带，研究耐热输送带的高温粘合反应特征，包括影响高温粘合的因素、基于覆盖胶导温条件下的覆盖胶厚度设计和模拟现场高温条件的粘合强度试验技术三项内容。根据EPDM、SBR和NR橡胶及硫化体系的反应机理，结合基体橡胶种类和分子结构对硫化体系（硫化剂、促进剂和活化剂）用量进行化学衡算和试验验证。研究表明，EPDM4045的最优交联度占到其活化基团的5%左右；SBR1502/NR的最佳交联度占到其活化基团的2%左右，硫磺硫化和含硫化合物硫化的交联剂用量系数完全一致。研究了带体结构对175℃层间粘合强度的影响。研究表明，采用EPDM覆盖胶+EPDM/NR芯胶双重结构时，覆盖胶-1st帆布层界面的常温和175℃粘合强度均达到标准规定。采用EPDM覆盖胶+EPDM/SBR粘合胶+NR/SBR芯胶三重结构时，覆盖胶-1st帆布层界面的175℃粘合界面不稳定且粘合强度不能达到标准规定，主要原因是EPDM/SBR粘合胶不能同时和EPDM覆盖胶、NR/SBR芯胶两个界面得到好的平衡。研究了强力帆布的175℃热稳定、热老化和热粘合性能。研究表明， EA型帆布（聚对苯二甲酸乙二酯纤维+聚己二酰己二胺纤维）、AA2型帆布（聚己二酰己二胺纤维+聚己二酰己二胺纤维）和AA型帆布（聚己内酰胺纤维+聚己内酰胺纤维）及输送带试样的175℃热稳定性能顺序是AA2=EA>AA；热老化性能顺序是AA2=EA>AA；热粘合性能顺序是AA2=AA>EA。AA2型帆布具有综合最优的耐热性能。研究了EPDM覆盖胶和EPDM/NR芯胶弹性体复合材料的物理性能、热老化性能、硫化性能及对常温/175℃层间粘合强度的影响。研究表明，在175℃×96h老化条件下，规格为300mm×300mm×12mm的EPDM覆盖胶试样，其热老化性能变化率能较好地达到标准要求；规格为300mm×300mm×6mm的EPDM覆盖胶试样远不能达到标准要求。说明EPDM覆盖胶本身具有较好的耐热老化性能，其与空气∕氧气接触的深度是影响热老化性能的关键。BET比表面积为160-180m2/g的白炭黑、马来酸酐络合丁二烯、液体三元乙丙橡胶、RA-RF粘合体系都对增进界面常温/高温粘合强度具有积极作用。重点研究了耐热输送带175℃粘合强度影响因素。在30℃-175℃范围内研究了实验温度与界面粘合强度的关系，发现随着实验温度的升高粘合强度迅速下降。系统实验了覆盖胶、芯胶、粘合胶及强力帆布对175℃粘合强度的影响，发现影响175℃粘合强度的最关键因素是强力帆布的材料组份，与浸胶EA型帆布相比，AA2型帆布与覆盖胶界面的高温粘合强度提高到了79%。间甲白粘合体系的配合比例对覆盖胶的物理性能具有重要影响,RA-65/RF最佳配合比例为1/1.2-1/1.4。通过建立数学模型的方式研究了基于覆盖胶导温条件下覆盖胶厚度、界面温度和界面粘合强度的对应关系。研究表明对于一定厚度的覆盖胶来说，导温速度与导温时间基本呈直线线性关系；对于不同厚度的覆盖胶来说其导温速率截然不同，覆盖胶越厚其导温速率越小，覆盖胶越薄其导温速率越大；与颗粒状物料相比，粉末状物料的导温速率明显偏大。提出了基于导温条件下满足输送带高温运行层间粘合强度的覆盖胶厚度设计方法。提出并研究了耐热输送带模拟现场高温条件下粘合强度的试验技术，并与GB/T20021粘合强度的试验技术特征做了实验对比。结果得出，175℃条件下，采用GB/T20021方法测定的粘合强度值远远小于模拟方法的测定值。分析认为模拟现场粘合强度的试验方法更能真实地测定粘合强度，更能准确地判定输送带的现场可用性。本文研制的新型T4/175℃耐热输送带，各项性能指标符合GB/T20021-2005标准，耐175℃稳定性能、老化性能和粘合性能突出。该产品取得国家权威部门的检验合格证书，并在高温物料现场得到应用。该产品申请了国家发明专利并取得实用新型专利证书。技术水平属于国际领先。更多还原

【Abstract】 The paper focus on developing neo-type heat-resistant conveyor belt of T4/175℃whichconforms to GB/T20021-2005, and studying three core characteristics including factorsinfluencing high-temperature-adhesion, temperature-conducting characteristic of the coverrubber and testing-technology characteristic of the adhesion strength simulating on-line hotmaterials.The reaction mechanism is studied,which include rubbers as EPDM,SBR and NR, as wellas vulcanization system. The amount of the materials such as curing agent, accelerator andactivator in vulcanization system is calculated on the basis of reaction mechanism, species ofrubber and molecular structure of rubber. Series of experiment have been done to verificate theaccurateness about the method of quantitative calculation.Influence of structure design on adhesion strength of the heat resistant conveyor belt at175℃has been studied. Research shows, adhesion strength between cover rubber and1stfabricmeet the standared both at room temperature and at175℃,which conveyor belt is made ofEPDM cover rubber and EPDM/NR core rubber.Fabrics used as carcass of heat-resistant conveyor belt are studied on its heat-stablityproperty, heat-aging property and heat-adhesion property for diffrent time at175℃. Researchshows, fabric of AA2-type has the best heat-resistant properties and it’s suited to be as carcass ofneo-type heat-resistant conveyor belt.Comprehesive properties of EPDM cover rubber and EPDM/NR core rubber elastomermaterials are studied,such as physical property, heat-aging property, curing property andadhesion strength between layers of the heat-resistant conveyor belt both at room temperatureand at175℃. Research shows that depth of EPDM cover rubber contact with the air/oxygen isthe key factor to the aging-resistant property at175℃.Focused on the characteristics and mechanism of adhesive reaction as well as influencingfactors to interfaces of heat-resistant conveyor belt at175℃. Results shows elementalcomposition of fabric is the most critical factor to adhesion strength at175℃. Compared withthe dipped EA-type fabric, adhesion strength at175℃between AA2-type fabric and EPDMcover rubber has been increased to179%.Corresponding relation among thickness of the cover rubber, interface temperature andadhesion strength has been studied through building mathematical model and testingtemperature-conducting characteristics of EPDM cover rubber for heat-resistant conveyorbelt.Research showed that the relationship about temperature-conducting-rate andtemperature-conducting-time is assume like a straight line to cover rubber with certain thickness.A new experimental technology of testing adhesion strength is studied which imitateson-line conditions with hot materials on heat-resistant conveyor belt. Experimental dates throughthe two different methods has been analysised. Results shows that the experimental technologyimitating on-line could test adhesion strength of belt with hot materials more authentically.The neo-type heat-resistant conveyor belt of T4/175℃developed in this paper has met thestandard of GB/T20021-2005. The new production has excellent quality in stabilityperformance, adhesion performance and aging performance at175℃. Both certificate ofinspection and certificate of patent by authorities have been obtained.更多还原