Sacrificial binders for molding particulate solids and the molding thereof

Claim 1

The method of making a sinterable molding of particulate sinterable particles which comprises mixing about 30 to about 70 volume percent of sinterable particulate solids with about 70 to about 30 volume percent of an organic sacrificial binder which comprises an intimate mixture of about 10 to about 90 parts by weight of resinous material and about 90 to about 10 parts by weight of a plasticizer for said resinous material wherein (1) said resinous material is a block polymer having the structural formula X--B(AB).sub. η A].sub.η' wherein "η" is 0 or a positive integer, X is a linking group, A or B, "η'" is a positive integer greater than 2, "A" is a linear or branched polymer that is glassy or crystalline at 20°-25° C. and has its softening point in the range of about 80° C. to about 250° C. and "B" is a polymer of different chemical composition than A that behaves as an elastomer at temperatures between 5° C. below the softening point of A and about 120° C. above the softening point of A; and (2) said plasticizer is selected from the group consisting of (a) an oil at least 75 percent by weight of which boils in the range of about 550° F. to about 1038° F., has viscosity at 210° F. in the range of about 30 to about 220 Saybolt Universal Seconds and aniline point in the range of about 170° F. to about 255° F. (b) a wax melting at a temperature in the range of about 130° F. to about 170° F. at least 75 percent by weight of which boils at temperatures in the range of about 600° F. to about 900° F., and (c) an oil in accordance with (a) and a wax in accordance with (b) and wherein 0 to between 49 and 50 weight percent of said block polymer is replaced by a first replacement polymer meeting the limitations of polymer "A" in said structural formula, and 0 to between 49 and 50 weight percent of said block polymer is replaced with a second replacement polymer meeting the limitations of polymer "B" in said structural formula, the sum of said replacements of said block polymer comprising in combination less than 50 weight percent of said block polymer, molding the resultant mixture, driving off said sacrificial binder from said mixture with heat and sintering said particulate solids of said mixture.

Claim 2

The method of making a sinterable molding of particulate sinterable particles which comprises mixing about 30 to about 70 volume percent of sinterable particulate solids with about 70 to about 30 volume percent of an organic sacrificial binder which comprises an intimate mixture of about 10 to about 90 parts by weight of resinous material and about 90 to about 10 parts by weight of a plasticizer for said resinous material wherein (1) said resinous material is a block polymer having the structural formula X--B(AB).sub. η A].sub.η' wherein "η" is 0 or a positive integer, X is a linking group, A or B, "η'" is a positive integer greater than 2, "A" is a linear or branched polymer that is glassy or crystalline at 20°-25° C. and has its softening point in the range of about 80° C. to about 250° C. and "B" is a polymer of different chemical composition than A that behaves as an elastomer at temperatures between 5° C. below the softening point of A and about 120° C. above the softening point of A; and (2) said plasticizer is selected from the group consisting of (a) an oil at least 75 percent by weight of which boils in the range of about 550° F. to about 1038° F., has viscosity at 210° F. in the range of about 30 to about 220 Saybolt Universal Seconds and aniline point in the range of about 170° F. to about 255° F. (b) a wax melting at a temperature in the range of about 130° F. to about 170° F. at least 75 percent by weight of which boils at temperatures in the range of about 600° F. to about 900° F., and (c) an oil in accordance with (a) and a wax in accordance with (b) and wherein 0 to between 49 and 50 weight percent of said block polymer is replaced by a first replacement polymer meeting the limitations of polymer "A" in said structural formula, and 0 to between 49 and 50 weight percent of said block polymer is replaced with a second replacement polymer meeting the limitations of polymer "B" in said structural formula, the sum of said replacements of said block polymer comprising in combination less than 50 weight percent of said block polymer, molding the resultant mixture, driving off said sacrificial binder from said mixture with heat and sintering said particulate solids of said mixture.

Claim 6

The method of making a sinterable molding of particulate sinterable particles which comprises mixing about 30 to about 70 volume percent of sinterable particulate solids with about 70 to about 30 volume percent of an organic sacrificial binder which comprises an intimate mixture of about 10 to about 90 parts by weight of resinous material and about 90 to about 10 parts by weight of a plasticizer for said resinous material wherein (1) said resinous material is a block polymer having the structural formula X--B(AB).sub. ηA].sub.η ' wherein "η" is 0 or a positive integer, X is a linking group, A or B, "η'" is a positive integer greater than 2, "A" is a linear or branched polymer that is glassy or crystalline at 20°-25° C. and has its softening point in the range of about 80° C. to about 250° C. and "B" is a polymer of different chemical composition than A that behaves as an elastomer at temperatures between 5° C. below the softening point of A and about 120° C. above the softening point of A; and (2) said plasticizer is selected from the group consisting of (a) an oil at least 75 percent by weight of which boils in the range of about 550° F. to about 1038° F., has viscosity at 210° F. in the range of about 30 to about 220 Saybolt Universal Seconds and aniline point in the range of about 170° F. to about 255° F. (b) a wax melting at a temperature in the range of about 130° F. to about 170° F. at least 75 percent by weight of which boils at temperatures 600°the range of about 600° F. to about 900° F., and (c) an oil in accordance with (a) and wax in accordance with (b) and wherein 0 to between 49 and 50 weight percent of said block polymer is replaced by a first replacement polymer meeting the limitations of polymer "A" in said structural formula, 0 to between 49 and 50 weight percent of said block polymer is replaced with a second replacement polymer meeting the limitations of polymer "B" in said structural formula, and 0 to between 49 and 50 weight percent of said block polymer is replaced with an elastomer polymer having the structural formula AB-- (AB)--η A wherein "η" is 0 or a positive integer and "A" and "B" have the same limitations as A and B of said block polymer except that "B" of said elastomer polymer behaves as an elastomer at a temperature between about 5° C. below and about 100° C. above the softening point of A of said block polymer, the sum of said replacements of said block polymer comprising less than 50 weight percent of said block polymer, molding the resultant mixture, driving off said sacrificial binder with heat and sintering said particulate solids of said mixture.

Claim 7

The method of making a sinterable molding of particulate sinterable particles which comprises mixing about 30 to about 70 volume percent of sinterable particulate solids with about 70 to about 30 volume percent of an organic sacrificial binder which comprises an intimate mixture of about 10 to about 90 parts by weight of resinous material and about 90 to about 10 parts by weight of a plasticizer for said resinous material wherein (1) said resinous material is a block polymer having the structural formula X--B(AB).sub. ηA].sub.η ' wherein "η" is 0 or a positive integer, X is a linking group, A or B, "η'" is a positive integer greater than 2, "A" is a linear or branched polymer that is glassy or crystalline at 20°-25° C. and has its softening point in the range of about 80° C. to about 250° C. and "B" is a polymer of different chemical composition than A that behaves as an elastomer at temperatures between 5° C. below the softening point of A and about 120° C. above the softening point of A; and (2) said plasticizer is selected from the group consisting of (a) an oil at least 75 percent by weight of which boils in the range of about 550° F. to about 1038° F., has viscosity at 210° F. in the range of about 30 to about 220 Saybolt Universal Seconds and aniline point in the range of about 170° F. to about 255° F. (b) a wax melting at a temperature in the range of about 130° F. to about 170° F. at least 75 percent by weight of which boils at temperatures 600°the range of about 600° F. to about 900° F., and (c) an oil in accordance with (a) and wax in accordance with (b) and wherein 0 to between 49 and 50 weight percent of said block polymer is replaced by a first replacement polymer meeting the limitations of polymer "A" in said structural formula, 0 to between 49 and 50 weight percent of said block polymer is replaced with a second replacement polymer meeting the limitations of polymer "B" in said structural formula, and 0 to between 49 and 50 weight percent of said block polymer is replaced with an elastomer polymer having the structural formula AB-- (AB)--η A wherein "η" is 0 or a positive integer and "A" and "B" have the same limitations as A and B of said block polymer except that "B" of said elastomer polymer behaves as an elastomer at a temperature between about 5° C. below and about 100° C. above the softening point of A of said block polymer, the sum of said replacements of said block polymer comprising less than 50 weight percent of said block polymer, molding the resultant mixture, driving off said sacrificial binder with heat and sintering said particulate solids of said mixture.