Poly(vinyl acetal) resin compositions, layers and interlayers having enhanced properties
Resin compositions, layers, and interlayers comprising a poly(vinyl acetal) resin that includes residues of an aldehyde other than n-butyraldehyde are provided. Such compositions, layers, and interlayers can exhibit enhanced or optimized properties as compared to those formulated with comparable poly(vinyl n-butyral) resins.
1. An interlayer comprising: a resin layer comprising a poly(vinyl acetal) resin and a plasticizer, wherein said poly(vinyl acetal) resin comprises residues of n-butyraldehyde and at least 50 weight percent of residues of at least one aldehyde other than n-butyraldehyde, based on the total weight of aldehyde residues of said poly(vinyl acetal) resin, and wherein said plasticizer is present in said resin layer in an amount sufficient to provide said resin layer with a glass transition temperature greater than 30° C.
2. The interlayer of claim 1 , wherein said plasticizer is present in said resin layer in an amount in the range of from 5 to 30 phr and wherein the glass transition temperature of said resin layer is at least 37° C.
3. The interlayer of claim 1 , wherein said plasticizer is present in said resin layer in an amount in the range of from 5 to 20 phr and wherein the glass transition temperature of said resin layer is at least 46° C.
4. The interlayer of claim 1 , wherein said plasticizer is present in said resin layer in an amount in the range of from 5 phr to 20 phr and wherein the glass transition temperature of said resin layer is at least 50° C.
5. The interlayer of claim 1 , wherein said plasticizer is present in said resin layer in an amount of not more than 10 phr and wherein the glass transition temperature of said resin layer is at least 65° C.
6. The interlayer of claim 1 , wherein said poly(vinyl acetal) resin comprises at least 50 weight percent of said residues of at least one aldehyde other than n-butyraldehyde, based on the total weight of aldehyde residues of said poly(vinyl acetal) resin, and wherein said resin layer further comprises a second poly(vinyl acetal) resin blended with said poly(vinyl acetal) resin, wherein said second poly(vinyl acetal) resin comprises at least 50 weight percent of residues of n-butyraldehyde, based on the total weight of said aldehyde residues of said second poly(vinyl acetal) resin, wherein each of said first and said second poly(vinyl acetal) resins are present in said resin layer in an amount of at least about 5 weight percent, based on the combined weight of said first and said second poly(vinyl acetal) resins.
7. The interlayer of claim 1 , wherein said poly(vinyl acetal) resin has a weight average molecular weight of at least 80,000 Daltons.