Claims
- 1. An ethynyl terminated ester oligomer for producing a cured polymer having improved solvent resistance, higher use temperature and synthesized according to the general reaction ##STR6## where PE refers to the polyester radical portion,
- n is an integer and represents 4 to 100 repeat units, base refers to an organic base selected from the group consisting of triethylamine, pyridine, quinoline, diethylamine and piperidine,
- R is selected from the group of radicals consisting of ##STR7## and mixtures thereof, and R' is selected from the group of radicals consisting of ##STR8## and mixtures thereof.
- 2. A cured polymer formed from the ethynyl terminated ester oligomer of claim 1 by casting the oligomer into a film and heating the cast film in the temperature range of approximately 250.degree. for thirty minutes.
- 3. A method for preparing an ethynyl-terminated polyarylate comprising:
- (a) dissolving a quantity of an hydroxy-terminated polyarylate in a solvent selected from the group consisting of ethonol-free chloroform, methylene chloride and N,N-dimethylacetamide and containing at least an equimolar quantity of an organic base selected from the group consisting of triethylamine, pyridine, quinoline, diethylamine, and piperidine,
- (b) dissolving at least an equimolar quantity of an ethynylbenzoyl chloride in a solvent also selected from the group of solvents listed above and adding the resultant to the stirred solution of hydroxy-terminated polyarylate obtained in step (a) over a period of five minutes and continuing stirring for approximately three hours,
- (c) precipitating a polymer from the stirred solution,
- (d) washing the precipitate, and
- (e) drying the washed precipitate to recover a yield of ethynylbenzoyloxy-terminated polyarylate.
- 4. The method of preparing the ethynyl-terminated polyarylate of claim 3 wherein the hydroxy-terminated polyarylate has a number average molecular weight of approximately 2500 and the ethynylbenzoyl chloride is 4-ethynylbenzoyl chloride.
- 5. The method of preparing the ethynyl-terminated polyarylate of claim 3 wherein the recovered product has a number average molecular weight in the range of approximately 2500 to approximately 10,000.
- 6. The method of preparing the ethynyl-terminated polyarylate of claim 3 wherein the step of washing the precipitate includes washing the precipitate
- (a) once with a 5% sodium bicarbonate solution,
- (b) twice with distilled water, and
- (c) once with methanol.
- 7. The method of preparing the ethynyl-terminated polyarylate of claim 3 wherein the molar ratio of raw ingredients comprise:
- 0.0040 mole hydroxy-terminated polyarylate (2500-M.sub.n),
- 0.012 mole triethylamine, and
- 0.012 mole 4 ethynylbenzoyl chloride to yield an approximately 88% yield recovery of 2500-M.sub.n ethynyl-terminate polyarylate.
- 8. The method of preparing the ethynyl-terminated polyarylate of claim 3 wherein the molar ratio of raw ingredients comprise:
- 0.00133 mole (7500-M.sub.n) hydroxy-terminated polyarylate,
- 0.0040 mole triethylamine, and
- 0.0040 mole 4-ethynylbenzoyl chloride to yield an approximately 95% yield recovery of 7500-M.sub.n ethynyl-terminated polyarylate.
- 9. An ethynyl-terminated ester oligomer formed as the reaction product of an hydroxy-terminated ester oligomer and 4-ethynylbenzoyl chloride.
- 10. The ethynyl-terminated ester oligomer of claim 9 having a number average molecular weight in the range of 2500-10,000.
- 11. A polymer film formed from the ethynyl-terminated ester oligomer of claim 10 by casting the oligomer into a film and heating the cast film at approximately 250.degree. C. for thirty minutes to effect crosslinking and oligomer chain extension.
- 12. A method of increasing the solvent resistance and T.sub.g of 4-ethynylbenzoyloxy-terminated polyarylate (ETPA) by thermally reacting 70-90% by weight thereof with 10-30% by weight of 2,2-bis(4,ethynylbenzoyloxy-4-phenyl) propane to yield a material having improved solvent resistance and a higher T.sub.g than that of the ETPA alone.
- 13. The method of claim 12 wherein the 4-ethynylbenzoyloxy-terminated polyarylate has a g/mole molecular weight in the range of 2500-10,000.
- 14. The method of claim 12 wherein the 2,2-bis(4-ethynylbenzoyloxy-4'-phenyl) propane and 4-ethynylbenzoyloxy-terminated polyarylate thermal reaction product is made into a m-cresol solution comprising 15% solids content (weight/volume),
- doctored onto plate glass as a film and stage dried in air at increasing temperature intervals to reach 250.degree. C. in approximately 30 minutes to yield a flexible, transparent, insoluble yellow film.
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of work under a NASA contract and is subject to the provisions of Section 305 of the National Aeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 435; 42 USC 2457).
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
3666023 |
Kehr et al. |
May 1972 |
|
4221895 |
Woo |
Sep 1980 |
|
4440945 |
Conciatori et al. |
Apr 1984 |
|