Ultraviolet (UV) curing of phosphated polyurethane-acrylic dispersions

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dc.contributor.authorMequanint K.
dc.contributor.authorSanderson R.D.
dc.date.accessioned2011-05-15T15:57:12Z
dc.date.available2011-05-15T15:57:12Z
dc.date.issued2003
dc.description.abstractPhosphate-containing polyurethane-acrylic dispersions were synthesised for UV curing studies. The effects of light intensity, substrate-dependent temperature increase, soft-segment content and water on conversion were investigated. The effect of the light intensity on conversion was twofold. At first, conversion increased with light intensity. This was attributed to the inability of shrinkage to keep pace with the polymerisation and crosslinking, resulting in the creation of free volume, thereby facilitating reaction and enhanced conversion. At higher intensities, conversion was found to be reversed or, at least, it remained constant, owing to increasing radical-radical termination reactions. Phosphated-polyurethane coatings with high soft-segment content show improved conversion with exposure time. This was found to be related to the chain mobility, caused by the low glass transition temperature of the soft segment. The effect of water on conversion was also twofold. On the one hand, water had a plasticising effect on the UV curing and the polymerisation rate was fast. On the other hand, the gel content was found to be lower when films were cured before the evaporation of water.
dc.description.versionConference Paper
dc.identifier.citationMacromolecular Symposia
dc.identifier.citation193
dc.identifier.issn10221360
dc.identifier.other10.1002/masy.200390050
dc.identifier.urihttp://hdl.handle.net/10019.1/10274
dc.subjectAcrylics
dc.subjectCuring
dc.subjectDispersions
dc.subjectFree radical polymerization
dc.subjectGlass transition
dc.subjectPlastic coatings
dc.subjectUltraviolet radiation
dc.subjectLight intensity
dc.subjectPolyurethanes
dc.subjectacrylic acid
dc.subjectphosphate
dc.subjectpolyester
dc.subjectpolyurethan
dc.subjectresin
dc.subjectconference paper
dc.subjectfilm
dc.subjectlight
dc.subjectmaterial coating
dc.subjectpolymerization
dc.subjectsynthesis
dc.subjecttemperature sensitivity
dc.subjecttime
dc.subjectultraviolet radiation
dc.titleUltraviolet (UV) curing of phosphated polyurethane-acrylic dispersions
dc.typeConference Paper
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