Variance of adhesive strength and fracture mechanism of fibre/matrix joints

Air-activated acrylic adhesives are one-part, rapid room-temperature setting adhesives which cure by redox-initiated polymerisation of (meth)acrylate monomers. Their cure is triggered by ambient atmosphere and results in cured adhesive properties similar to conventional two-part acrylic adhesives. A test method developed using dynamic mechanical thermal analysis to characterise their cure behaviour was subsequently used in the assessment of the effects of ageing on the adhesives. The objective of this study is to investigate if the rate of cure of the adhesives retarded on storage at room temperature over a period of one year. Tubes of adhesive were tested at selected time intervals and the findings are reported and analysed using analysis of variance. It was found that over a 12 month period there was no ageing effect on the cure characteristics of air-activated adhesives.