POLYMER BLENDS FOR ROOFTOP CURABLE HEAT SEAMABLE ROOF SHEETING AND METHOD FOR COVERING ROOFS

摘要

A rooftop curable heat seamable sheet material for roofing prepared from an uncured polymeric composition of matter which comprises 100 parts by weight of apolymer blend comprising from about 10 to 95 parts by weight of an polymer selected from the group consisting of polyolefins having up to about 2 percent by weight crystallinity, which polyolefins are prepared from monomers having at least 2 carbon atoms, and mixtures thereof; from about 5 to 90 parts by weight of a crystallinity enhancing polymer and mixtures thereof; from about 20 to 300 parts by weight of a filler selected from the group consisting of reinforcing and non-reinforcing materials and mixtures thereof per 100 parts of the polymer blend; from about 1.5 to 10 parts by weight of a cure package a cure package capable of allowing the composition of matter to cure at temperatures of at least 50.degree.C, per 100 parts of the polymer blend; and from about 20 to 150 parts by weight of a processing material and mixtures thereof, per 100 parts of the polymer blend. A method for covering a roof comprises the steps of applying layers of self-adhering sheet material prepared from an uncured heat seamable polymeric composition of matter comprising blends of polyolefins with crystallinity enhancing polymers, fillers, processing material and a cure package capable of allowing the composition of matter to cure at temperatures of at least 50.degree.C to the roof being covered; overlapping adjacent edges of the layers; heating the overlapped areas to about the softening point of the sheet material and seaming the overlapped areas undersufficient pressure to provide an acceptable seam strength. The composition of matter is curable at temperatures of at least about 50.degree.C, at temperature readily encountered on the roof of a building. For practice of the method, the composition of matter is selfadhering, without the use of an adhesive.