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This paper reports a study on the effect of silicon carbide nanoparticles on the adhesion strength of steel–glass/epoxy composite joints bonded with two-part structural acrylic adhesives. The introduction of nanosilicon carbide in the two-part acrylic adhesive led to a remarkable enhancement in the shear and tensile strength of the composite joints. The shear and tensile strengths of the adhesive joints increased with adding the filler content up to 1.5 wt%, after which decreased with adding more filler content. Also, addition of nanoparticles caused a reduction in the peel strength of the joints. DSC analysis revealed thatTgvalues of the adhesives rose with increase in the nanofiller content. The equilibrium water contact angle was decreased for adhesives containing nanoparticles. SEM micrographs revealed that addition of nanoparticles altered the fracture morphology from smooth to rough fracture surfaces. [ABSTRACT FROM AUTHOR]

The effect of reducing the molar mass of the shell layer of core–shell latex particles on film-forming and final coating properties of self-crosslinking latexes was investigated. Latex particles were prepared by the semi-continuous non-seeded emulsion polymerization of methyl methacrylate, butyl acrylate and methacrylic acid as main monomers. The particle core was slightly cross-linked (using a constant amount of allyl methacrylate as a comonomer) to prevent the copolymers forming the core phase from migration into the shell phase. For interfacial cross-linking, diacetone acrylamide was copolymerized into the shell layer of latex particles to provide sites for subsequent reaction with adipic acid dihydrazide. The molar mass of copolymers forming the shell layer was systematically varied by isooctyl 3-mercaptopropionate chain transfer agent included in the synthesis of each of the shell layers and the molar mass distribution was determined using size exclusion chromatography coupled with a multi-angle light scattering detection. Fundamental properties of latexes and cast films were systematically compared. These properties included minimum film-forming temperature, pendulum hardness, adhesion, impact resistance, stress–strain properties as well as the characterization of water absorption. The results confirmed theoretical predictions and described empirically the effects of reducing the molar mass of the shell layer copolymer on final properties of coating films. [ABSTRACT FROM AUTHOR]

Wood connections made with high-performance pressure sensitive adhesive (PSA) tapes have significant promise for mitigating damage in buildings under high wind or seismic conditions. Benefits may include improved joint ductility and sealing protection from water-intrusion damage from hurricanes. In this work a series of connection tests were performed primarily on acrylic PSA tapes in accordance with ASTM D 1761-88 (2000). Performance results for PSA tape/wood joints are presented and trends examined for comparisons of commercial PSA tapes from three manufacturers. The results also provided implementation data on required application pressure levels and time duration, and comparisons with adhesive connection types. Specific parameters were discussed and examined using statistical methods to quantitatively determine performance gains or losses. The variables investigated included the use of oriented strand board (OSB) versus plywood sheathing, the effect of priming and surface sanding on adhesion, and a comparison of connections involving mechanical fasteners with those that utilized only adhesive tape or a combination of the two. Properly bonded OSB and plywood connections provided fairly ductile failure modes. The overall results of the study suggest that the International Building Code (IBC) ban on construction adhesives for shear walls in high seismic zones could be lifted for high-performance acrylic PSA tapes. [ABSTRACT FROM AUTHOR]