Structural laminate and method for making same

A process for producing a structural laminate comprising the steps of:

• I. contacting a thin, substantially incompressible mat of glass fibers with a foam-forming mixture comprising:
• A. a mixture of polymethylene polyphenyl isocyanates of Formula I:
• ##STR3## wherein n is an integer from 0 to 8 inclusive, and B. a diol having an equivalent weight of 30 to 100 of Formula II:
• ho--r.sup.1 --oh (ii)
• wherein R.sup.1 is selected from the group consisting of lower alkylene and lower alkoxyalkylene.
• wherein the equivalent ratio of A:B is 2:1 to 6:1,
• Ii. positioning a facing sheet comprising a metal on each face of the mat,
• Iii. passing the facing sheets having the mat of glass fibers and the foam-forming mixture there between through the nip of two rotating rolls wherein:
• A. the thickness of the mat remains substantially the same as prior to passing through the nip,
• B. the velocity of the mat is equal to the velocity of the facing sheets,
• C. the glass fibers of the mat are arranged in layers,
• D. the glass fibers within each layer are substantially parallel,
• E. the glass fibers in each layer are at an acute angle to the glass fibers in each next adjacent layer, and
• F. the foam-forming mixture completely fills the interstices between the fibers of the mat, and
• Iv. permitting the foam-forming mixture to expand under the influence of heat generated in an exothermic reaction between the components of the mat separating under the sole influence of the expansion of the foam-forming mixture, the layers of fibers in the mat maintaining their same order but being distributed throughout the resultant structural laminate.

A process for producing a structural laminate comprising the steps of:

• I. contacting a thin, substantially incompressible mat of glass fibers with a foam-forming mixture comprising:
• A. a mixture of polymethyl polyphenyl isocyanates of Formula I:
• ##STR4## wherein n is an integer from 0 to 8 and the polyisocyanates have an equivalent weight of 120 to 180 and a functionality of 2.5 to 3.5 and the mixture has a viscosity of 250 to 2500 centipoises;
• B. diethylene glycol, wherein the equivalent ratio of A:B is between 3.0:1 and 5.0:1;
• C. a catalyst composition in an amount and of a type sufficient to give the foam-forming mixture a cream time between 15 to 20 seconds and a firm time between 25 and 60 seconds;
• D. fluorotrichloromethane in an amount from 5 to 20 weight percent based on the weight of the foam-forming mixture;
• E. a surfactant in an amount from 0.1 to 2.0 weight percent based on the weight of the foam-forming mixture.
• Ii. positioning a facing sheet comprising a metal foil between 0.010 and 0.001 inches thick on each face of the mat,
• Iii. passing the facing sheets having the mat of glass fibers and the foam-forming mixture there between through the nip of two rotating rolls wherein:
• A. the thickness of the mat before passing through the nip of the two rotating rolls is between 0.010 and 0.050 inches,
• B. the thickness of the mat immediately after passing through the nip remains substantially the same as prior to passing through the nip,
• C. the velocity of the mat is equal to the velocity of the facing sheets,
• D. the glass fibers of the mat are arranged in layers,
• E. the glass fibers within each layer are substantially parallel,
• F. the glass fibers in each layer are at an angle of less than 60.degree. to the glass fibers in each next adjacent layer,
• G. the glass fibers are attached to one another by an amount of fiber binder sufficient to make the mat of glass fibers dimensionally stable but insufficient to fill the interstices between the glass fibers and insufficient to resist the expansion of the glass fibers under the influence of the expansion of the foam-forming mixture,
• H. the fibers forming the mat are wetable by the foam-forming mixture to the extent that the foam-forming mixture will penetrate and completely fill the interstices between the glass fibers of the mat,
• I. the foam-forming mixture completely fills the interstices between the fibers of the mat,
• J. the glass fibers of the mat have an average length that exceeds five feet.
• Iv. passing the facing sheets having the mat and the foam forming mixture therebetween from the nip of the two rotating rolls into an expansion zone wherein:
• A. the facing sheets having the mat and the foam-forming mixture therebetween are subjected to the influence of heat controlably added by the circulation of hot air for regulating the expansion of the foam-forming mixture,
• B. the foam-forming mixture expands under the influence of the heat added by the hot air and under influence of heat generated in an exothermic reaction between the components of the foam-forming mixture,
• C. the layers of the fibers in the mat separate under the sole influence of the expansion of the foam-forming mixture,
• D. the layers of the fibers in the mat maintain their same order but are distributed throughout the resultant structural laminate in planes substantially parallel to the planes of the facing sheets,
• V. curing the foam-forming mixture at a temperature of 175.degree. F. to 250 .degree. F. until the resultant structural laminate is rigidly self supporting,
• Vi. periodically severing the structural laminate into finite lengths thereby forming discrete panels.

A structural laminate comprising:

• A. at least one planar facing sheet;
• B. a rigid foam integrally attached upon formation of the foam to one surface of the facing sheet, the rigid foam formed from a foam-forming mixture comprising:
• I. an organic polyisocyanate, and
• Ii. a diol having an equivalent weight between 30 to 100;
• C. a mat of glass fibers wherein:
• I. the glass fibers of the mat are distributed substantially evenly throughout the rigid foam,
• Ii. the glass fibers are straight,
• Iii. the glass fibers are long,
• Iv. the glass fibers of the mat are arranged in layers,
• V. each layer of glass fibers is substantially parallel to the facing sheet.
• Vi. the rigid foam completely fills the interstices between the glass fibers of the mat, the glass fibers being held in fixed relationship with respect to each other solely by the rigid foam.

A structural laminate comprising:

• A. two planar facing sheets;
• B. a rigid foam integrally attached upon formation of the foam between the facing sheets, the rigid foam formed from a foam-forming mixture comprising:
• I. a mixture of polymethylene polyphenyl isocyanates of Formula a:
• ##STR6## wherein n is an integer from 0 to 8 inclusive, and II. a diol having an equivalent weight of 30 to 100 of Formula b:
• Ho--r.sup.1 --oh (b)
• wherein R.sup.1 is selected from the group consisting of lower alkylene and lower alkoxyalkylene,
• wherein the equivalent ratio of I:II is 2:1 to 6:1,
• C. a mat of glass fibers wherein:
• I. the glass fibers of the mat are distributed substantially evenly throughout the rigid foam,
• Ii. the glass fibers are non-crimped,
• Iii. the glass fibers are long,
• Iv. the glass fibers of the mat are arranged in layers,
• V. each layer of glass fibers is substantially parallel to the facing sheet,
• Vi. the glass fibers within each layer are substantially parallel,
• Vii. the glass fibers in each layer are at an acute angle to the glass fibers in each next adjacent layer and
• Viii. the foam-forming mixture completely fills the interstices between the fibers of the mat, the fibers being held in fixed relationship with respect to each other solely by the rigid foam.

A structural laminate comprising:

• A. two planar facing sheets wherein:
• I. each facing sheet is a metal foil between 0.010 and 0.001 inches thick,
• Ii. the surface of one facing sheet observe to that attached to the rigid foam is decoratively embossed;
• B. a rigid foam integrally attached upon formation of the foam to one surface of each facing sheet, the rigid foam formed from a foam-forming mixture comprising:
• I. a mixture of polymethyl polyphenyl isocyanates, of Formula a:
• ##STR7## wherein n is an integer from 0 to 8 and the polyisocyanates have an equivalent weight of 120 to 180 and a functionality of 2.5 to 3.8 and the mixture has a vecosity of 250 to 2500 centipoises;
• Ii. diethylene glycol, wherein the equivalent ratio of I:II is between 3.0:1 and 5.0:1;
• Iii. a catalyst composition in an amount and of a type sufficient to give the foam-forming mixture a cream time between 15 and 20 seconds and a firm time between 25 and 60 seconds;
• Iv. fluorotrichloromethane in an amount from 5 to 20 weight percent based on the weight of the foam-forming mixture;
• V. a surfactant in an amount from 0.1 to 2.0 weight percent based on the weight of the foam-forming mixture.
• C. a mat of glass fibers wherein:
• I. the glass fibers of the mat are distributed substantially evenly throughout the rigid foam,
• Ii. the glass fibers are non-crimped,
• Iii. the glass fibers have an average length that exceeds five feet,
• Iv. the glass fibers of the mat are arranged in layers,
• V. each layer of glass fibers is substantially parallel to the facing sheet,
• Vi. the glass fibers within each layer are substantially parallel,
• Vii. the glass fibers in each layer are at an angle of less than 60.degree. to the glass fibers in each next adjacent layer, and
• Viii. the foam-forming mixture completely fills the interstices between the fibers of the mat, the fibers being held in fixed relationship to each other solely by the rigid foam,
• Ix. the mat of glass fibers being included in the amount of 6-20 gms. per board-foot of structural laminate.