Thermally insulating batt and composite

Abstract

The present invention relates to a thermally insulating batt comprising: (i) 10 to 70% by weight staple flash spun plexifilamentary fibers or staple melt spun fibrillated fibers; (ii) 10 to 70% by weight staple fibers; and (ii) 5 to 30% by weight binding agent that can also be used in a thermally insulating composite suitable for use in exterior portions of residential and commercial buildings.

What is claimed is: 
     
         1 . A thermally insulating batt comprising:
 (i) 10 to 70% by weight of the total batt of a collection of first staple fibers that comprise staple flash spun plexifilamentary fibers or staple melt spun fibrillated fibers or both;   (ii) 10 to 70% by weight of the total batt of a collection of second staple fibers; and   (iii) 5 to 30% by weight of the batt of binding agent.   
     
     
         2 . The thermally insulating batt of  claim 1 , wherein the first staple fibers are present at 25 to 60% by weight of the total batt, the second staple fibers are present at 25 to 60% by weight of the total batt, and the binding agent is present at from 15 to 25% by weight of the total batt. 
     
     
         3 . The thermally insulating batt of  claim 2 , wherein the first staple fibers are present at 35 to 60% by weight of the total batt, the second staple fibers are present at 35 to 60% by weight of the total batt. 
     
     
         4 . The thermally insulating batt of  claim 1 , wherein between 5 to 50% of the second staple fibers have a weight of less than 3.0 denier per filament. 
     
     
         5 . The thermally insulating batt of  claim 1 , wherein the staple flash spun plexifilamentary fibers have a surface area of 10 m 2 /g or less or a crush value of at least 1 mm/g or both. 
     
     
         6 . The thermally insulating batt of  claim 5 , wherein the surface area is less than 5 m 2 /g or the crush value is at least 1.5 mm/g or both. 
     
     
         7 . The thermally insulating batt of  claim 1 , wherein the staple flash spun plexifilamentary fibers comprise a polyolefin polymer. 
     
     
         8 . The thermally insulating batt of  claim 7 , wherein the polyolefin polymer is polyethylene. 
     
     
         9 . The thermally insulating batt of  claim 1 , wherein the staple melt spun fibrillated fibers comprise a polyolefin polymer, polyester polymer, polyamide polymer or mixtures thereof. 
     
     
         10 . The thermally insulating batt of  claim 1 , wherein the staple fibers comprise a polyester polymer, polyolefin polymer, polyamide polymer or viscose rayon. 
     
     
         11 . The thermally insulating batt of  claim 10 , wherein the polyester polymer is polyethylene terephthalate. 
     
     
         12 . The thermally insulating batt of  claim 1 , wherein first staple fiber comprises a thermoplastic polymer and the binding agent comprises at least one polymeric component with a melting point below the melting point of the thermoplastic polymer. 
     
     
         13 . The thermally insulating batt of  claim 12 , wherein the binding agent is in the form of staple binder fibers. 
     
     
         14 . The thermally insulating batt of  claim 1 , wherein the first staple fibers comprise a thermoplastic polymer and the binding agent is in the form of staple binder fibers that comprise multiple polymeric components with (a) a first polymeric component with a melting point below the melting point of the thermoplastic polymer and that occupies at least a portion of a surface of the staple binder fibers and (b) a second polymeric component with a melting point above that of the first polymeric component and with a melting point below that of the thermoplastic polymer. 
     
     
         15 . The thermally insulating batt of  claim 1 , wherein the thermally insulating batt has a thermal conductivity/basis weight ratio at 0.0318 meters thickness, of less than 7.5×10 −5  (W/m·K)/(g/m 2 ). 
     
     
         16 . A thermally insulating composite comprising:
 (a) a thermally insulating batt comprising:
 (i) 10 to 70% by weight of the total batt of a collection of first staple fibers that comprise staple flash spun plexifilamentary fibers or staple melt spun fibrillated fibers; 
 (ii) 10 to 70% by weight of the total batt of a collection of second staple fibers; and 
 (iii) 5 to 30% by weight of the batt of binding agent and 
   (b) a substrate adjacent to one surface of the thermally insulating batt wherein the substrate has a Gurley Porosity between 250 and 5990 sec/100 cubic centimeters/inch 2  a moisture vapor transmission rate (MVTR) of between 250 and 1870 grams/meter 2 /24 hours and a hydrostatic head of between 200 and 400 centimeters of water.   
     
     
         17 . The thermally insulating composite of  claim 16 , wherein 5 to 50% of the staple fibers weigh less than 3.0 denier per filament. 
     
     
         18 . The thermally insulating composite of  claim 16 , wherein the thermally insulating batt has a thermal conductivity/basis weight ratio at 0.0318 m thickness, of less than 7.5×10 −5  (W/m·K)/(g/m 2 ). 
     
     
         19 . The thermally insulating composite of  claim 16 , wherein the substrate is a nonwoven comprising flash spun plexifilamentary fibers. 
     
     
         20 . An exterior portion of a building comprising the thermally insulating batt of  claim 1 . 
     
     
         21 . An exterior portion of a building comprising the thermally insulating composite of  claim 16 .