Modified copolymer latex binder

Abstract

A modified copolymer latex binder comprising a styrene-butadiene latex and a urea-formaldehyde resin that may be used in preparation of polyester fiber mats that are useful in the roofing industry.

What is claimed is:  
     
         1 . A modified copolymer latex binder for polyester fibers comprising at least 10 wt %-90 wt % styrene-butadiene and a corresponding amount of 90 wt %-10 wt % of a urea-formaldehyde resin wherein the urea-formaldehyde resin is prepared by adding a short-stop agent to the urea-formaldehyde resin reaction system.  
     
     
         2 . The modified copolymer latex binder of  claim 1  wherein the latex binder comprises about 70 wt % styrene-butadiene and about 30 wt % of a urea-formaldehyde resin.  
     
     
         3 . The modified copolymer latex binder of  claim 2  wherein the styrene-butadiene latex comprises about 10-90 wt % styrene and about 90-10 wt % butadiene modified by a cross-linking agent.  
     
     
         4 . The modified copolymer latex binder of  claim 3  wherein the styrene-butadiene latex comprises about 30-70 wt % styrene and about 70-30 wt % butadiene modified by a cross-linking agent.  
     
     
         5 . The modified copolymer latex binder of  claim 3  wherein the styrene-butadiene latex comprises about 40 wt % styrene and about 60 wt % butadiene modified by a cross-linking agent.  
     
     
         6 . A sheet comprising a single layer of nonwoven or woven polyester mat coated with a binder composition including at least 10 wt %-90 wt % styrene-butadiene latex and 90 wt %-10 wt % urea-formaldehyde wherein the urea-formaldehyde resin is prepared by adding a short-stop agent to the urea-formaldehyde resin reaction system.  
     
     
         7 . The sheet of  claim 6  wherein the latex binder comprises about 70 wt % styrene-butadiene and about 30 wt % of a urea-formaldehyde resin.  
     
     
         8 . The sheet of  claim 6  wherein the styrene-butadiene latex comprises about 10-90 wt % styrene and about 90-10 wt % butadiene modified by a cross-linking agent.  
     
     
         9 . The sheet of  claim 6  wherein the styrene-butadiene latex comprises about 30-70 wt % styrene and about 70-30 wt % butadiene modified by a cross-linking agent.  
     
     
         10 . The sheet of  claim 6  wherein the styrene-butadiene latex comprises about 40 wt % styrene and about 60 wt % butadiene modified by a cross-linking agent.  
     
     
         11 . A roofing shingle, comprising: 
 an asphalt-coated polyester mat embedded with granules, said polyester mat comprising a plurality polyester fibers bonded with a modified styrene-butadiene latex modified with a urea-formaldehyde resin, wherein the urea-formaldehyde resin is prepared by adding a short-stop agent to the urea-formaldehyde resin reaction system.    
     
     
         12 . The roofing shingle of  claim 11  wherein the latex comprises about 70 wt % styrene-butadiene and about 30 wt % of a urea-formaldehyde resin.  
     
     
         13 . The roofing shingle of  claim 12  wherein the latex comprises about 10-90 wt % styrene and about 90-10 wt % butadiene modified by a cross-linking agent.  
     
     
         14 . The roofing shingle of  claim 13  wherein the latex comprises about 30-70 wt % styrene and about 70-30 wt % butadiene modified by a cross-linking agent.  
     
     
         15 . The roofing shingle of  claim 13  wherein the latex comprises about 40 wt % styrene and about 60 wt % butadiene modified by a cross-linking agent.