层间接触条件对沥青路面高温性能的影响

通过力学计算和室内试验研究了层间接触条件对沥青路面高温性能的影响.应用BISAR计算了不同层间接触条件下的沥青面层剪应力,通过直剪试验测定了洒布不同粘层材料的复合马歇尔试件的抗剪强度,采用车辙试验测定复合式车辙板的DS和总变形量.研究结果表明：完全光滑的层间接触条件大幅提高了沥青面层的最大剪应力,并加速了沥青面层发生剪切破坏而出现车辙;粘层提高了层间抗剪强度,不同的粘层材料对层间接触条件的改善效果不同;高抗剪强度的层间接触能提高复合式车辙板的高温性能;采取适当措施改善层间接触条件,对提高沥青路面的高温性能具有重要意义.     

粘贴式外墙外保温施工

从基层墙面清理、粘结层厚度、网格布铺贴、抗裂层厚度、外装涂饰层等方面对粘贴式外墙外保温的施工过程控制进行了详细阐述,以确保外墙外保温工程的施工质量。     

2-Ethylhexyl acrylate/4-acryloyloxy benzophenone copolymers as UV-crosslinkable pressure-sensitive adhesives

Summary It has been previously shown that copolymer of 2-ethylhexyl acrylate with an 4-acryloyloxy benzophenone can be used as PSA. This paper presents synthesis and application of solvent-based polymer system for the preparation of acrylic pressure-sensitive adhesives (PSA). 2-Ethylhexyl acrylate benzophenone copolymers, having molecular mass in the range of 120 000 to 380 000 Dalton were prepared by free-radical solution polymerization. These copolymers were tacky but possessed insufficient cohesive strength after UV-crosslinking to be useful as PSAs. These copolymers resulted in materials having a balance of cohesive and adhesive characteristics required of a good PSA. Some of the parameters affecting the pressure-sensitive adhesive properties of the copolymer are: amount of the 4-acryloyloxy, molecular mass of the polymeric components, UV-reactivity and such properties like tack, peel adhesion and cohesion.     

Viscoelastic Properties of Pressure-Sensitive Adhesives

Recent studies on the correlation of viscoelastic properties of pressure-sensitive adhesive (PSAs) with industry standard performances such as peel, tack and shear are reviewed and discussed. One notewothy feature in these correlations is the separation of the bonding and debonding steps in PSA adhesion, which specifies the characteristic bonding and debonding frequencies of different PSA tests. Viscoelastic windows (VW) for different types of pressure-sensitive adhesives (PSAs) proposed by these workers are also compared and discussed. The observed good correlations reaffirm the importance of bulk viscoelastic properties to PSA adhesion performances.     

Effect of zinc oxide on the viscosity,tack, and peel strength of ENR 25‐based pressure‐sensitive adhesives

Viscosity, loop tack, and peel strength of epoxidized natural rubber (ENR 25 grade)‐based pressure‐sensitive adhesive was studied in the presence of zinc oxide. The zinc oxide concentration was varied from 10–50 parts per hundred parts of rubber (phr). Coumarone–indene resin with loading from 20 to 100 phr was chosen as the tackifier resin. Toluene was used as the solvent throughout the experiment. The adhesive was coated on the substrate using a SHEEN hand coater to give a coating thickness of 60 μm. Viscosity of the adhesive was determined by a HAAKE Rotary Viscometer whereas the loop tack and peel strength were measured by a Llyod Adhesion Tester operating at 30 cm/min. Results show that viscosity and loop tack of adhesive increases with increasing zinc oxide concentration. For the peel strength, it increases with zinc oxide concentration up to 30–40 phr and drops after the maximum value. This observation is associated with the effect of varying degree of wettability of the adhesive on the substrate. However, for a fixed zinc oxide concentration, loop tack and peel strength exhibit maximum value at 80 phr resin loading after which both properties decrease with further addition of resin, an observation which is attributed to phase inversion. From this study, the optimum adhesion property is achieved by using 40 phr zinc oxide and 80 phr coumarone–indene resin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

热熔压敏胶粘接性能的流变学研究

研究了苯乙烯嵌段共聚物系热熔压敏胶的动态流变学行为和持粘力之间的联系,主要研究了决定持粘力的流变学参数.研究证明,持粘力受到体系的蠕变过程的控制,可以通过较高温度下得到的持粘力数据来预测室温持粘力的大小.研究了液体树脂含量对持粘力的影响,提出损耗角正切(tan δ)最小值及其对应的温度是决定热熔压敏胶持粘力的关键流变学参数.     

不同点固焊形式对焊接变形和残余应力的影响

借助有限元分析手段对不同点固焊形式的对接焊焊接过程进行模拟,经分析得到焊接变形和应力分布情况,采用实验手段验证试验结果。结果表明,点固焊位置相同,长度越长,获得的变形量越小;起、收弧的两端面点固焊变形在起、收弧两侧翘起,焊缝位置点固焊翘起的位置发生在与焊缝位置平行的两侧自由端;点固焊长度越长,仿真和实测结果的残余应力分布波动性越大;在起、收弧两端面点固焊获得的残余应力峰值最小;起、收弧两端面点固焊、点固焊2处残余应力值均降低,点固焊3处残余应力值增大。证明了有限元模型的正确性和有效性。     

印刷油墨粘性的理论分析与测量

印刷油墨的粘性对提高印刷质量和效率有重要影响,本文阐述了雷德式油墨粘性测量系统的结构与组成,采用高精度力传感器有效解决了粘性测量问题,精度可达到0.01N,分析了油墨流变学特性与粘性测量系统的动力学过程,得到了油墨粘性值的实用估算公式并通过实验验证。结果表明:油墨粘性值与转速成线性,与温度成指数关系。研究结果为油墨的生产和使用提供了理论与实验依据。     

粘贴式外墙外保温施工过程控制

从基层墙面清理、粘结层厚度、网格布铺贴、抗裂层厚度、外装涂饰层等方面对粘贴式外墙外保温的施工过程控制进行了详细阐述，以确保外墙外保温工程的施工质量。     

浅谈自粘橡胶沥青防水卷材粘结层的配方设计思想

介绍了自粘橡胶沥青防水卷材粘结层的配方设计思想，分析了胶粘剂的组成。