INFLUENCE OF FLUOROACRYLATE CURE SITE MONOMER ON THE THERMAL AND MECHANICAL PROPERTIES OF THE POLYACRYLIC ESTER ELASTOMER

ABSTRACT The rubber industry is facing strong challenges in recent times because of imposed stringent standards on the performance of a product under adverse thermal and chemical applications. The choice of proper elastomer plays a significant role in imparting useful product performance. A new type of acrylic rubber with a fluoroacrylate cure site monomer was developed. Structural characterization, such as Fourier-transform infrared spectroscopy and nuclear magnetic resonance (NMR), suggested the presence of four different monomer units. Two-dimensional NMR spectroscopy analysis was also performed to support the assessment of the resonance peaks of coupled nuclei spins in the terpolymer. The newly developed acrylic rubber exhibited superior thermal and mechanical properties. Hexamethylenediamine carbamate in combination with zinc oxide (ZnO) was used as the curing package for the new elastomer. ZnO acts as an acid scavenger to avoid the micro-void formation. The new elastomer with a higher number of cross-link junctions resulted in superior mechanical and thermal properties as well as swelling resistance of the vulcanizate both with and without carbon black.

Influence of polyacrylic ester and silica fume on the mechanical properties of mortar for repair application

Experimental investigations on the influence of different amounts of polyacrylic ester and silica fumes on the mechanical properties of mortar such as the compressive strength, splitting tensile strength, bonding strength, and abrasion resistance are presented in this article. The results show that the compressive and splitting tensile strength of mortar can be improved with the addition of polyacrylic ester and silica fumes. Results obtained from both the direct tensile bond test and flexural bond test indicate that the addition of polyacrylic ester and silica fumes improves the bond strength significantly, and the enhancement is more obvious with polyacrylic ester paste as interfacial adhesives. Furthermore, mortar incorporation of polyacrylic ester and silica fumes shows superior abrasion resistance compared to the control mortar. Therefore, the correct combination of polyacrylic ester and silica fumes to produce mortars has been shown to have synergistic effects, which results in excellent properties including high bond strength and superior abrasion resistance. Mortars containing polyacrylic ester and silica fumes are ideal for repairing concrete especially for hydraulic concrete structure.