Study on the Tensile Strength and Adhesive Properties of the Copolyester for High Temperature Application

고온재료용 코폴리에스터의 강도 및 접착특성 연구

  • 김연철 (천안공업대학 신소재응용화학과)
  • Published : 2004.02.01

Abstract

Thermosetting copolyester adhesives were prepared by copolymerizing p-hydroxybenzoic acid (HBA), 6-hydroxy-2-naphthoic acid (HNA) and 4-functional crosslinkable oligomers. Two different crosslinkable oligomers having four carboxylic acid or four acetoxy end groups were evaluated. The transition from thermoplastic to thermosetting character occurred when 10 wt% oligomer was added to the 73/27 HBA/HNA copolyester. Tensile strength and lap shear strength of the copolyesters have been investigated by both tensile test and adhesive test using an aluminum sheet. In the case of tensile strength of a single fiber, the values for the copolyesters containing oligomer decreased to about 90% of the 73/27 HBA/HNA fiber in the high draw ratio region while a slight decrease in tensile strength was observed in the low draw ratio region. An adhesive test using aluminum sheet revealed a decrease in the lap shear strength up to 15$0^{\circ}C$ for all copolyesters except the copolyester containing 10 wt% crosslinkable oligomer. Compared to 73/27 HBA/HNA copolyester, an improvement in the lap shear strength of the copolyesters containing 5 wt% oligomer was observed up to 15$0^{\circ}C$. On the other hand, the copolyester containing 10 wt% crosslinkable oligomer displayed a small change in the lap shear strength with temperature.

Keywords

References

  1. Angew. Chem. Int. Ed. Engl. v.29 Advanced Materials: Trends and Possibilities in Liquid Crystalline Polymers J.Economy https://doi.org/10.1002/anie.199012561
  2. American Chemical Society National Critical Technologies Report J.Oleson
  3. Electrical-Electronic and Liquid Crystal Polymer Engineering Plastics Division
  4. Processing of Polymer Liquid Crystals High Modulus Polymers: Approaches to Design and Development D.N.Lewis;J.F.Fellers
  5. Macromolecules v.32 The Degradation Process Observed during Step Annealing of 73/27 HBA/HNA Copolyester Y.C.Kim;J.Economy https://doi.org/10.1021/ma981552t
  6. J. Korean Fiber Soc. v.40 Study on the Preparation and Stepwise Annealing of Thermotropic Copolyester Fibers Y.C.Kim
  7. Thesis, University of Illinois at Urbana-Champaign High Temperature Behavior of Aromatic Liquid Crystalline Copolyesters Based on 4-Hydroxybenzoic Acid C.W.Potter
  8. Ph. D. Thesis, University of Illinois at Urbana-Champaign Design of Improved Polyester Dielectric Insulators for Electronic Packaging L.A.Schneggenburger
  9. Macromolecules v.28 Effect of Annealing on the Physical Properties of Biaxially Oriented Liquid Crystalline Copolyester Films S.M.Hong;J.Economy https://doi.org/10.1021/ma00123a014
  10. Poly. for Adv. Techn. v.10 The Effect of Branching on the Physical Properties of 73/27 HBA/HNA Y.C.Kim;J.Economy https://doi.org/10.1002/(SICI)1099-1581(199909)10:9<535::AID-PAT906>3.0.CO;2-8
  11. Liquid Crystal Polymers A.V.Volokhina;G.I.Kudryavtsev
  12. Polymer v.38 Thermally Crosslinkable Thermotropic Copolyesters: Synthesis, Characterization and Processing P.T.Mather;K.P.Chaffee;A.Romo-Uribe https://doi.org/10.1016/S0032-3861(97)00162-6
  13. J. of Rheology v.35 Transient and Steady Rheological Behavior of the Thermotropic Liquid Crystal Copolymer 73/27 F.Cocchini;M.R.Nobile;D.Acierno https://doi.org/10.1122/1.550170
  14. Macromolecules v.24 High-Temperature Recrystallization and Rheology of a Thermotropic Liquid Crystalline Polymer Y.G.Lin;H.H.Winter
  15. Macromolecules v.29 Log-Rolling Alignment in Main-Chain Thermotropic Liquid Crystalline Polymer Melts under Shear: An In-Situ WAXS Study A.Romo-Uribe;A.H.Windle https://doi.org/10.1021/ma960211h
  16. J. of Adhesion v.37 Liquid Crystalline Copolyester as High Temperature Adhesives for Aluminium J.Economy;T.Gogeva;V.Habbu https://doi.org/10.1080/00218469208033069
  17. J. of Adhesion v.40 Factors which Influence the High Temperature Adhesives Characteristics of Liquid Crystalline Copolyester J.Economy;A.G.Andreopoulos https://doi.org/10.1080/00218469308031278