LAUSR

Films of ethylene–vinyl acetate copolymer (EVA) with different vinyl acetate (VA) contents were adopted as flexible substrates for fabrication of micro-pyramid arrays by roll-to-roll hot embossing at roller temperatures 40–80 °C. An empirical relationship between rheological behavior of EVA in rubbery state and demolding performance of the films was explored. Dependence of average forming height of micro-pyramid arrays on VA content and roller temperatures was investigated. Our study showed that both viscosity and relaxation behavior of EVA can be related to the ultimate forming height of micro-pyramids. The relationships can provide references for experimental research and industrial manufacture on roll-to-roll hot embossing. Retroreflection of micro-pyramid arrays was observed and transmittances of the two sides of embossed films were studied. Transmittances of the VA28 film embossed at 60 °C were 97.9% (the embossed side) and 41.8% (the smooth side), which showed potential applications in reflective film and anti-reflective film fields. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45228.