TY - JOUR ID - 16148 TI - Polymeric number average molecular weight in submicron films as a tool for the manipulation of water phenomena in translucent coatings JO - Advanced Materials Proceedings JA - AMP LA - en SN - 2002-4428 AU - Lopez-Barbosa, Natalia AU - F. Osma, Johann AD - CMUA, Department of Electrical and Electronics Engineering, Universidad de los Andes, Cra. 1E No. 19a – 40, Bogota, DC 111711, Colombia. Y1 - 2018 PY - 2018 VL - 3 IS - 6 SP - 392 EP - 395 KW - Polymeric films KW - water phenomena KW - average molecular weight DO - 10.5185/amp.2018/900 N2 - Absorption and desorption properties of poly(ethylene glycol) diacrylate (PEGDA) have seen to greatly vary depending on the molecular weight of the polymer, suggesting a dependence of the wetting phenomena on its molecular weight. Here, two sets of polymeric submicron films (140 and 190 nm) were fabricated by free radical polymerization using Phenylbis (2, 4, 6-trimethylbenzoyl) phosphine oxide as the photoinitiator, and PEGDA (Mn 250 or 575). The films were spin coated on glass substrates to study their wetting phenomena by dynamic contact angle analysis. All films were characterized in terms of their thickness and transmittance. PEGDA Mn 250 films (Film-250) decreased the sliding time of water drops when compared to a clean glass substrate because of a decrement in the liquid-solid interface area. Nonetheless, when using PEGDA Mn 575 films (Film-575), an improvement in the adhesion forces between the coating and the drop of water was observed, avoiding the drop to slide down the substrate and leading to its later evaporation. In addition, Film-575 drastically changed their morphology after water exposure, while Film-250 remained the same. These characteristics are of special interest in environments where a response towards small amounts of water is desired, or where water evaporation is craved. Copyright © 2018 VBRI Press. UR - https://amp.iaamonline.org/article_16148.html L1 - https://amp.iaamonline.org/article_16148_c1ed62c8065d614e22261f9dc2c265b3.pdf ER -