Miscibility,Morphology and Tensile Properties of the Melt Blends of Liquid Crystalline Polyimide (PI-LC) with Two Different Thermoplastic Polyimides: Semicrystalline Polyimide (N-TPI) and Amorphous Poly(Ether-Imide) (PEI)

Abstract

A liquid crystalline polyimide (poly[1, 3-bis[4-(4-aminophenoxy)-α, α-dimethylbenzyl]benzene pyromellitimide]: PI-LC) was blended with two kinds of thermoplastic polyimide: poly[3, 3′-(4, 4′-dioxybiphenyl)diphenylene pyromellitimide] (N-TPI) which is a semicrystalline polyimide having a melting point of 388 °C and poly[2, 2′-bis(3, 4-dicarboxyphenoxy)phenylpropane-2-phenylene bisimide] (PEI) which is an amorphous poly(etherimide) having a glass transition temperature at 220 °C. The miscibility of N-TPI and PI-LC was evaluated by DSC using enthalpy relaxation, and the phase diagram of their blend was drawn above the melting point of N-TPI. The result indicated that the PI-LC-rich blend was miscible in a wide range of compositions. However, the extruded samples of their blend, which had been prepared under a flow of high shear, showed a phase separation structure. In the other combination of PEI and PI-LC, the blend was immiscible, but at low composition of PI-LC their blend fibre showed higher tensile properties than the original PEI fibre.

Get full access to this article

View all access options for this article.

References

[1] Inoue T 1996 Polym. Prepr. Japan. 45 979-979

[2] Ouyanagi Y and Harada T 1991 Super-Enpura-Kei Polymer Alloy (Tokyo: Gihodo)

[3] Kochi M , Uruji T , Iizuka T and Mita I 1987 J. Polym. Sci. Polym. Lett. 25 441-441

[4] Jou J-H and Huang P-T 1990 Polym. J. 22 909-909

[5] Fukai T , Yang J C , Kyu T , Cheng S Z D , Lee S K , Hsu S L C and Harris F W 1992 Polymer 33 3621-3621

[6] Harris J E and Robeson L M 1988 J. Appl. Polym. Sci. 35 1877-1877

[7] Bafna S S , Sun T and Baird D G 1993 Polymer 34 708-708

[8] Bretas R E S and Baird D G 1992 Polymer 33 5233-5233

[9] Bretas R E S , Collias D and Baird D G 1994 Polym. Eng. Sci. 34 1492-1492

10.

[10] Morales A R and Bretas R E S 1996 Eur. Polym. J. 32 349-349

11.

[11] Morales A R and Bretas R E S 1996 Eur. Polym. J. 32 365-365

12.

[12] Friler J and Cebe P 1993 Polym. Eng. Sci. 33 587-587

13.

[13] Huo P P , Friler J B and Cebe P 1991 Mater. Res. Soc. Symp. Proc. 227 239-239

14.

[14] Huo P P , Friler J B and Cebe P 1993 Polymer 34 4387-4387

15.

[15] Huo P P and Cebe P 1993 Polymer 34 696-696

16.

[16] Aihara Y and Cebe P 1992 Polym. Prepr. 33 471-471

17.

[17] Ma S P , Sasaki T , Sakurai K and Takahashi T 1994 Polymer 35 5618-5618

18.

[18] Takahashi T , Yuasa S , Tsuji M and Sakurai K 1994 J. Macromol. Sci-Phys. B 33 63-63

19.

[19] Okuyama K , Sakaitani H and Arikawa H 1992 Macromolecules 25 7261-7261

20.

[20] Tsutsumi T and Morita A 1993 Kobunshi Kako, Japan 28 340-340

21.

[21] Morita A , Furukawa H and Koba T 1993 Proc. 3rd Japan. Int. SAMPE Symp. p 779-779

22.

[22] Bosma M , Brinke G T and Ellis T S 1988 Macromolecules 21 1465-1465

23.

[23] Hildebrand J H and Scott R S 1964 Solubility of Nonelectrolytes (New York: Dover)

24.

[24] Fedors R F 1974 Polym. Eng. Sci. 14 147-147

25.

[25] Saito H , Matsuura M , Okada T and Inoue T 1989 Polym. J. 21 357-357

26.

[26] Tanaka M , Konda M , Miyamoto M , Kimura Y and Yamaguchi A High Perform. Polym. 10 147-153

27.

[27] Utracki L A 1991 Polymer Alloy and Polymer Blend Trans. T Nishi (Tokyo: Tokyo Kagaku Dojin)

28.

[28] Guerra G , Choe S , Williams D J , Karasz F E and MacKnight W J 1988 Macromolecules 21 231-231

29.

[29] Chen H-L 1995 Macromolecules 28 2845-2845