Polymer Bulletin, Vol.76, No.9, 4469-4483, 2019
Preparation and characterization of the acrylic latex-laminating adhesives applied in BOPP/PE composite films
Acrylic latex-laminating adhesives (ALLAs) were successfully prepared via the monomer-starved seeded semi-continuous emulsion copolymerization with butyl acrylate-methyl methacrylate-acrylamide (BA-MMA-Am) monomers, and only 1.1wt% emulsifier contents were employed. The effect of Am on final latex, the dried latex films, and adhesive properties of ALLAs were discussed by utilizing rotational viscometer, dynamic light scattering, transmission electron microscopy, Fourier transform infrared spectrometer, contact angle, differential scanning calorimeter, thermogravimetric analysis (TG), and mechanical experiments, respectively. The results indicated that the peel strength of the biaxial-oriented polypropylene/polyethylene composite films can reach a peak (3.15N/15mm) at the content of 2wt% Am in the pre-emulsion feed, which satisfies an acceptable minimum peel strength (0.8N/15mm) for application. Additionally, average particle size of the final latex experienced few changes, but the particle size distribution of the latex changed notably as Am contents varied from 0 to 10wt%, while T-g of ALLAs increased gradually, and the molecular weight (M-n and M-w) increased obviously. TG results showed that the ALLAs have excellent thermal stability with a high decomposition temperature of 300 degrees C.
Keywords:Acrylic latex-laminating adhesives;Adhesive properties;Acrylamide;Peel strength;Emulsion polymerization