Claims
- 1. A shape memory polymer resin, consisting essentially of a block copolymer having an A-B-A block structure in the polymer chain, and having a weight average molecular weight within the range of 10,000 to 1,000,000, wherein
- (a) block A is a polymer block comprising a homopolymer of a vinyl aromatic compound, a copolymer of a vinyl aromatic compound and another vinyl aromatic compound, a copolymer of a vinyl aromatic compound and a conjugated diene compound, and/or a hydrogenated product thereof;
- (b) block B is a polymer block comprising a homopolymer of butadiene, a copolymer of butadiene with another conjugated diene compound, a copolymer of butadiene with a vinyl aromatic compound, and/or a hydrogenated product thereof, the content of butadiene and/or the hydrogenated product thereof in block B being at least 80% by weight, and 80 to 91% of the linkages of the butadiene and/or the hydrogenated product thereof being 1,4-linkages;
- (c) at least 80% by weight of the conjugated diene in the block copolymer being hydrogenated; and
- (d) the block copolymer comprises 5 to 50% by weight of said block A; and
- wherein said polymer resin having the following properties (1) to (3):
- (1) the glass transition temperature Ta of the phase containing block A and the crystalline melting point Tb of the phase containing block B, having the relationship shown by the following formula:
- 25.degree. C..ltoreq.Tb<Ta.ltoreq.150.degree. C.,
- (2) the crystallinity of the phase containing block B at 25.degree. C. being at least 5% by weight; and
- (3) said polymer resin being compressible by at least 1/4-fold of the original thickness at a temperature of (Ta+Tb)/2, and at least 70% of the deformation being fixed by cooling the compressed product to 25.degree. C., and at least 90% of said deformation fixed being restored by reheating to a temperature exceeding (Ta+Tb)/2.
- 2. The shape memory polymer resin according to claim 1, wherein the block copolymer has a linear type block structure, a radial type block structure or a graft type block structure represented by the formulae:
- (a) (A-B).sub.n A
- (b) B(A-B).sub.n A
- (c) B(A-B).sub.n A-B
- (d) [(A-B).sub.n ].sub.m X
- (e) [(A-B).sub.n A].sub.m X
- (f) [B(A-B).sub.n ].sub.m X
- (g) [B(A-B).sub.n A].sub.m X ##STR4## wherein n is an integer of 1 to 10, m is an integer of 2 to 10, and X is a terminal coupling agent.
- 3. The shape memory polymer resin according to claim 1, wherein the weight average molecular weight (Mw) of the total block copolymer is within the range of 15,000 to 300,000.
- 4. The shape memory polymer resin according to claim 1, wherein the content of the vinyl aromatic compound or its hydrogenated product in block A is at least 70% by weight.
- 5. The shape memory polymer resin according to claim 1, wherein the content of butadiene or a hydrogenated product thereof in block B is at least 95% by weight.
- 6. The shape memory polymer resin according to claim 1, wherein the content of the 1,4-linkage in the linkage of butadiene in block B is within the range of 83 to 90%.
- 7. The shape memory polymer resin according to claim 1, wherein at least 90 mole % of the conjugated diene in block B is hydrogenated.
- 8. The shape memory polymer resin according to claim 1, wherein at least 95 mole % of the conjugated diene in block B is hydrogenated.
- 9. The shape memory polymer resin according to claim 1, wherein the vinyl aromatic compound in the block copolymer is styrene and/or .alpha.-methylstyrene.
- 10. The shape memory polymer resin according to claim 1, wherein the glass transition temperature Ta of the phase containing block A and the crystalline melting point Tb of the phase containing block B has the relationship of the following formula:
- 4.degree. C..ltoreq.Tb<Ta.ltoreq.130.degree. C.
- 11. The shape memory polymer resin according to claim 1, wherein the glass transition temperature Ta of the phase containing block A and the crystal melting point Tb of the phase containing block B has the relationship of the following formula:
- Ta-Tb>5.degree. C.
- 12. The shape memory polymer resin according to claim 1, wherein the crystallinity of the phase containing block B at 25.degree. C. is at least 10% by weight.
- 13. The shape memory polymer resin according to claim 1, further comprising 1 to 100 parts of an inorganic filler based on 100 parts by weight of said shape memory polymer resin.
Priority Claims (2)
Number |
Date |
Country |
Kind |
63-323267 |
Dec 1988 |
JPX |
|
1-284700 |
Nov 1989 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/454,264 filed on Dec. 21, 1989, abandoned, the entire contents of which are incorporated herein by reference.
US Referenced Citations (8)
Foreign Referenced Citations (7)
Number |
Date |
Country |
0234512 |
Feb 1987 |
EPX |
56-118403 |
Sep 1981 |
JPX |
60-079061 |
May 1985 |
JPX |
63-179955 |
Jul 1988 |
JPX |
63-179956 |
Jul 1988 |
JPX |
8603980 |
Jul 1986 |
WOX |
8301254 |
Apr 1983 |
WOX |
Continuations (1)
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Number |
Date |
Country |
Parent |
454264 |
Dec 1989 |
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