Float Glass Plates Research Articles

Adhesion Mechanisms of Polyurethanes to Glass Surfaces I. Structure-Property Relationships in Polyurethanes and Their Effects on Adhesion to Glass

Abstract Polyurethanes were prepared from toluene diisocyanate (TDI), 1-4-butane diol (BDO) and polycaprolactone-based triols with varying molecular weights. Among each molecular weight triol-based urethane, hard segment content was varied from 20% to 70%. Differential scanning calorimetry, tensile testing, and Iosipescu shear testing were done on all the various urethanes prepared. Thermal characterization data revealed the dependence of phase separation on hard segment content as well as on the triol molecular weight. Tensile data and Iosipescu shear data further confirmed the observations made from the DSC data. The data further indicated that phase separation can greatly improve the modulus of cross-linked segmented urethanes. Adhesion of these urethanes to glass surface was evaluated using soda-lime float glass plate. Urethane samples were cast on the air side of the glass plates and adhesion was measured in shear mode. Adhesion data indicated that in addition to hard segment content, modulus, cross-...

The fracture energy of glass

Abstract The fracture energy of Float and Pyrex glass plates has been determined in various media using a simple double-cantilever cleavage technique. Although slow growth of the crack at constant displacement of the cantilever arms was observed in all environments, consistent values for the energy expended when the crack propagates rapidly were obtained. This ‘instantaneous fracture energy’ranged from ∼5000 erg/cm2 (Float glass) or 6000 erg/cm2 (Pyrex) in vacuum to 2500 erg/cm2 (for both glasses) in water. The results are discussed in terms of Marsh's hypothesis that localized plastic flow occurs at the crack tip.