Aluminium-Aluminium Bonding by Rubber Blend Based on Epichlorohydrin Rubber and Carboxylated Nitrile Rubber

Rubber blends based on epichlorohydrin rubber and carboxylated nitrile rubber can be used as adhesives for aluminium-aluminium bonding. The bond strength depends on blend composition and moulding conditions, such as time, temperature and pressure. Lewis acid/base type interaction is responsible for this type of adhesion. The failure mechanism of the composites was studied by SEM.     

Aluminium-Aluminium Bonding by Rubber Blend Based on Epichlorohydrin Rubber and Carboxylated Nitrile Rubber

Rubber blends based on epichlorohydrin rubber and carboxylated nitrile rubber can be used as adhesives for aluminium-aluminium bonding. The bond strength depends on blend composition and moulding conditions, such as time, temperature and pressure. Lewis acid/base type interaction is responsible for this type of adhesion. The failure mechanism of the composites was studied by SEM.     

Reusable Dry Adhesive: Aluminium-Aluminium Bonding by Self-Vulcanisable Blend Based on Carboxylated Nitrile Rubber and Chlorobutyl Rubber

A self-vulcanisable blend of chlorobutyl rubber and carboxylated nitrile rubber can be used as an adhesive for aluminium-aluminium bonding. The peel strength depends on the state of cure of the adhesive, testing temperature and carboxyl content of the carboxylated nitrile rubber. At moulding times below 15 minutes, the adhesive was found to be reusable after repeated post-peel mouldings.     

Reusable Dry Adhesive: Aluminium-Aluminium Bonding by Self-Vulcanisable Blend Based on Carboxylated Nitrile Rubber and Chlorobutyl Rubber

A self-vulcanisable blend of chlorobutyl rubber and carboxylated nitrile rubber can be used as an adhesive for aluminium-aluminium bonding. The peel strength depends on the state of cure of the adhesive, testing temperature and carboxyl content of the carboxylated nitrile rubber. At moulding times below 15 minutes, the adhesive was found to be reusable after repeated post-peel mouldings.     

Peel stress relaxation of aluminium-aluminium joints bonded by chlorobutyl rubber-carboxylated nitrile rubber blend

The authors have introduced the concept of peel stress relaxation during 180° peel testing of an aluminium-adhesive-aluminium joint in order to explore the correlation, if any, between relaxation phenomenon and performance of the adhesive joint. The adhesive is based on a self-vulcanizable rubber blend of chlorobutyl rubber and carboxylated nitrile rubber. Peel stress relaxation depends on moulding time, silica filler loading, test temperature and peel rate. Peel stress relaxation mechanism varies depending on whether the adhesive joint failure is cohesive or interfacial.     

丁腈橡胶增韧改性环氧树脂的研究

通过羧基丁腈橡胶(XNBR)对双酚A环氧树脂(CYD-128)进行改性研究,制备了具有优良增韧效果的嵌段高分子预聚物。对制备过程的反应机理、合成条件、产品转化率等进行了比较深入的研究和探讨。结果表明:羧基丁腈橡胶与环氧树脂反应温度100～120℃、反应时间1.5～3h、催化剂用量0.20%～0.30%时,为最佳合成工艺;XNBR含量为15phr时,改性材料具有最大的断裂伸长率。     

Influence of Layered Double Hydroxides on the Curing of Carboxylated Nitrile Rubber with Zinc Oxide

Unmodified (LDH) and modified (mLDH) layered double hydroxides have been added to gum and ZnO‐cured carboxylated nitrile rubber (XNBR). It was observed that both LDH and mLDH inhibit the formation of ionic cross‐links between XNBR and ZnO quite significantly, as is evident from DMA and FT‐IR studies. The suppression of ionic cross‐links formation was also reflected in the mechanical properties of the resulting composites. A tentative sketch has also been suggested for the possible mechanism involved in the inhibition of ionic cross‐links by LDHs. X‐ray diffraction and STEM studies were performed to see the dispersion of LDH's in the elastomer matrix.

     

Peel Adhesion of Natural Rubber Bonded to Polyethylene Terephthalate: Effect of Crosslinking on Rate/Temperature Response

Laminates consisting of natural rubber (NR) sandwiched between cloth fabric and polyester film were pulled apart at various rates and temperatures in a T-peel geometry. Peel energies for joints containing uncrosslinked or lightly-crosslinked NR did not obey simple time-temperature superposition. This behavior is attributed to strain-induced crystallization during peeling. However, when the rubber was highly crosslinked, strain crystallization seems to be absent, as peel energies now can be WLF shifted to form a mastercurve.     

Peel Adhesion of Natural Rubber Bonded to Polyethylene Terephthalate: Effect of Crosslinking on Rate/Temperature Response

Laminates consisting of natural rubber (NR) sandwiched between cloth fabric and polyester film were pulled apart at various rates and temperatures in a T-peel geometry. Peel energies for joints containing uncrosslinked or lightly-crosslinked NR did not obey simple time-temperature superposition. This behavior is attributed to strain-induced crystallization during peeling. However, when the rubber was highly crosslinked, strain crystallization seems to be absent, as peel energies now can be WLF shifted to form a mastercurve.     

Effect of silica filler on aluminum-aluminum bonding by a self-vulcanizable blend based on chlorobutyl rubber and carboxylated nitrile rubber

Silica filler improves the aluminum-aluminum bonding by a self-vulcanizable rubber blend based on chlorobutyl rubber and carboxylated nitrile rubber. The joint peel strength depends on the filler loading, the state of cure, the molding temperature, and the adhesive film thickness. The higher peel strength in the filled adhesive system is due to filler reinforcement resulting in tear path deviation and the formation of Si—O—Al linkage at the aluminum-adhesive interface. Maximum peel strength was obtained at 10 phr filler loading, when the molding temperature was 180°C and the molding pressure was 0.35 MPa.     

Sensitivity and Optimization of Peel Strength Based on Composition of Adhesives for Footwear Industry

In order to contribute to the research and development of adhesives for the footwear industry, this paper aims to develop a model capable to predict and optimize the peel strength from the composition of adhesives. The proposed approach is based on three stages: experimental planning of measurements, global sensitivity analysis for uncertainty propagation, and optimization procedure. The design variables are the weight percentages of the solid raw material constituents such as polyurethane, resins, and additives of the adhesive joint. Considering the experimental results obtained for Taguchi design points as input/output patterns, an artificial neural network (ANN) is developed based on supervised evolutionary learning. Using the developed ANN a global sensitivity analysis procedure is implemented and the variability of the structural response of adhesive joint is studied. The optimal solution for adhesives composition for maximum peel strength is investigated based on ANN model and using a genetic algorithm. The proposed approach is able to predict the optimal peel strength including its sensitivity to uncertainties. The results show that the sensitivities of design variables belonging to polyurethane and additive groups are important for optimal adhesive joint. The optimal peel strength based on proposed approach is consistent with the experimental testing data.