Ultrathin polyarylate polymer films and their preparation

Claim 2

A polyarylate free-standing polymer film containing no macroscopic holes and having a thickness of about 180 angstroms or less and randomly oriented molecules.

Claim 3

The film of claim 1 wherein the film is prepared from a polymer having repeating units of the formula: ##STR4## where R is C 1 -C 6 alkylene.

Claim 4

The film of claim 2 wherein R is C 3 .

Claim 5

The film of claim 1 wherein the film is prepared from a polymer having repeating units of the formula: ##STR5##

Claim 6

The film of claims 1, 2, 3 or 4 wherein the film is prepared from a polyarylate polymer having a molecular weight, M w , greater than about 5,000.

Claim 7

The film of claim 5 wherein the film is prepared from a polyarylate polymer having a molecular weight, M w , greater than about 30,000.

Claim 8

The film of claims 1, 2, 3 or 4 wherein the film is prepared from a casting solution containing the polyarylate polymer at about the 80 to about the 100 percent by weight level and another polymer or polymers at about the 20 to about the 0 percent by weight level based upon the total weight of polymers dissolved in the casting solution.

Claim 9

A polyarylate polymer film containing no macroscopic holes and having a thickness of about 500 angstroms or less and randomly oriented molecules prepared according to the process comprising: (a) preparing a casting solution containing a polyarylate polymer in 1,2,3-trichloropropane at about three to about twelve percent by weight level based on the total weight of the casting solution; (b) depositing the casting solution on water to form a free-standing film; and (c) removing the film from the water.

Claim 10

A polyarylate polymer film containing no macroscopic holes and having a thickness of about 500 angstroms or less and randomly oriented molecules prepared according to the process comprising: (a) preparing a casting solution containing a polyarylate polymer in 1,2,3-trichloropropane at about three to about twelve percent by weight level based on the total weight of the casting solution; (b) depositing the casting solution on water to form a free-standing film; and (c) removing the film from the water.

Claim 11

The film of claim 8 wherein the polyarylate polymer has a molecular weight, M w , greater than about 5,000.

Claim 12

The film of claim 8 wherein the polyarylate polymer has a molecular weight, M w , greater than about 30,000.

Claim 13

The film of claim 8 wherein the film has a thickness of about 400 angstroms or less and wherein ortho-dichlorobenzene is employed in addition to 1,2,3-trichloropropane.

Claim 14

The film of claim 11 wherein about a 2:1 to about a 20:5 by volume mixture of 1,2,3-trichloropropane: ortho-dichlorobenzene is employed.

Claim 15

The film of claim 12 wherein the mixture is about a 20:7 by volume mixture of 1,2,3-trichloropropane:orthodichlorobenzene.

Claim 16

The film of claim 11 wherein ethylene chloride or dichloroethane is employed in addition to 1,2,3-trichloropropane and ortho-dichlorobenzene.

Claim 17

The film of claim 8 or 12 wherein the polyarylate polymer is present at about the five to about the ten percent by weight level in the casting solution based upon the total weight of the casting solution.

Claim 18

The film of claim 15 wherein the polyarylate polymer is present at about the seven to about the eight percent by weight level in the casting solution based upon the total weight of the casting solution.

Claim 19

The film of claims 8 or 11 wherein the polyarylate polymer has the recurring general formula: ##STR6## wherein R is C 1 -C 6 alkylene.

Claim 20

The film of cclaims 8 or 11 wherein the polyarylate polymer has the recurring general formula: ##STR7##

Claim 21

The film of claim 17 wherein R is C 3 .

Claim 22

A polyarylate polymer film containing no macroscopic holes and having a thickness of about 400 angstroms or less and randomly oriented molecules prepared according to the process comprising: (a) preparing a casting solution containing a polyarylate polymer having the general formula: ##STR8## at about the three to about the twelve percent by weight level based upon the total weight of the casting solution, in about a 2:1 to about a 20:5 by volume ratio of 1,2,3-trichloropropane:ortho-dichlorobenzene; (b) depositing the casting solution on water to form a free:standing film; and (c) removing the film from the water.

Claim 23

A polyarylate polymer film containing no macroscopic holes and having a thickness of about 400 angstroms or less and randomly oriented molecules prepared according to the process comprising: (a) preparing a casting solution containing a polyarylate polymer having the general formula: ##STR8## at about the three to about the twelve percent by weight level based upon the total weight of the casting solution, in about a 2:1 to about a 20:5 by volume ratio of 1,2,3-trichloropropane:ortho-dichlorobenzene; (b) depositing the casting solution on water to form a free:standing film; and (c) removing the film from the water.

Claim 24

The film of claim 20 wherein the ratio is about a 20:5 to about a 20:7 by volume ratio.

Claim 25

The film of claim 21 wherein the ratio is about 20:7.

Claim 26

The film of claim 20 wherein the polyarylate polymer has a molecular weight, M w , greater than about 5,000.

Claim 27

The film of claim 20 wherein the polyarylate polymer has a molecular weight, M w , greater than about 30,000.

Claim 28

The film of claim 20, 21 or 22 wherein the polyarylate polymer is present at about the five to about the ten percent by weight level in the casting solution based upon the total weight of the casting solution.

Claim 29

The film of claim 25 wherein the polymer is present at about the seven to about the eight percent by weight level.

Claim 30

The film of claim 8 or 20 wherein the casting solution contains a polyarylate polymer at about the 80 to about the 100 percent by weight level and another polymer or polymers at about the 20 to about the 0 percent by weight level based upon the total weight of the polymers dissolved in the casting solution.