Modification of Urea-Formaldehyde binder in fiberglass insulating mat by using of emulsion polymers

Urea-Formaldehyde resins are widely used in wet laid fiberglass roofing mat as a crosslinkable binder. Despite of the benefits of such resins, the disadvantages exist due to inadequate tensile and tear properties of the mat product. Two main routes are being used, chemical modification of UF resin during or after synthesis and mixing the resin with various materials such as water soluble polymers or polymeric emulsions. In this study different types of polymer emulsions were blended with UF resin which was subsequently employed as fiberglass mat binder. Acrylic, styrene-butadiene rubber (SBR) and polybutadiene rubber (PBR) emulsions were used and their effects on the gel time, mechanical and tear properties of the mats were investigated. It was found that by the addition of polymeric latex to the UF resin, the mechanical and tear properties of the resulting mats are significantly increased while the gel time is decreased for the SBR and PBR emulsions. However, the acrylic emulsion showed an increase in gel time. The later was attributed to the film formationability of the acrylic emulsion compared with the two other emulsions which prevent the water exudation during curing the UF resin. The morphology of the cured films was investigated by the scanning electron microscopy (SEM) of their fractured surface and a general coarser surface was observed in the modified UF resins