Epoxy Resin-modified,Urea-formaldehyde/Silicon Networks for High Impact Strength and Thermal Stability

Abstract

A variety of toughening agents are used to modify epoxy resins that improve the fracture toughness of the epoxy systems. The basic goal in toughening cross-linked epoxy resins that are normally brittle at room temperature is to improve crack resistance and toughness without significantly decreasing other important inherent properties, such as the flexural modulus and the thermomechanical properties of the original epoxy resins.

In the present study, thermally stable epoxy resin modified urea-formaldehyde/silicon blends have been prepared by in situ polymerization technique. The materials were modified with triethylenetetramine (hardener) to obtain highly cross-linked thermosetting resins. The physical properties of the resulting blends were evaluated by measuring the impact strength, which is found to be increased by more than 25% of that of the cured and blank epoxy resin. The impact fracture surfaces are examined using scanning electron microscopy (SEM) to reveal the morphological changes.

The hardness was found to be high in the case of modified epoxy resin as compared to blank epoxy. The influence on the thermal properties and the behavior of different curing agents on resins were investigated by thermogravimetrc analysis (TGA) and differential scanning calorimetry (DSC). The results of the modified epoxy resins showed remarkably high thermal stability as well as a higher degree of solvent resistance as compared with blank epoxy resin.

Keywords

epoxy resin solvent resistance mechanical properties thermogravimetric analysis differential scanning calorimetry.

Get full access to this article

View all access options for this article.

References

Hua Ren, Jian Zhong Sun, A. , Binjie Wu and Qiyun Zhou (2007). Synthesis and Properties of a Phosphorus-Containing Flam Retardant Epoxy Resin Based on Bis-Phenoxy(3-hydroxy)Phenyl Phosphine Oxide, Polymer Degradation and Stability, 92(6): 956-961.

Guoyuan Pana , Zhongjie Dua , Chen Zhanga , Congju Lib , Xiaopin Yanga and Hang Quan Li (2007). Synthesis Characterization, and Properties of Novel Novolac Epoxy Resin Containing Naphthalene Moiety, Polymer 48(13): 3686-3693.

Takao Iijima , Noriyuki Arai , Wakichi Fukuda and Masao Tomoi (1995). Toughening of Aromatic Diamine-Cured Epoxy Resins by Poly(ethylene phthalate)s and the Related Co Polyesters, European Polymer J., 31(3): 275-284.

Jyongsik Jang and Seunghan Shin (1995). Toughness Improvement of Tetra Functional Epoxy Resin by using Hydrolysed Poly(ether amide), Polymer, 36(6): 1199-1207.

Gue Yanga, B. , Shao-Yun Fu and Jiao-Ping Yang (2007). Preparation and Mechanical Properties of Modified Epoxy Resins with Flexible Amines, Polymer, 48(1): 302-310.

Marcad, L.A. , Galiáa, M. and Rina, J.A. ( 2006). Silicon-Containing Flame Retardant Epoxy Resins Synthesis, Characterization and Properties, Polymer Degradation and Stability , 91(11): 2588-2594.

Puglia, D. , Manfredi, L.B. , Vazquez, A. and Kenny, J.M. ( 2001). Thermal Degradation and Fire Resistance of Epoxy-Amine Phenolic Blends, Polymer Degradation and Stability, 73(3): 521-527.

Perrin, F.X. , Thi Minh Nguyen, B. , Thi My Linh Tran and Vernet, J.L. ( 2006). Determination of Bisphenol A (BPA) by Gas Chromatography-mass Spectrometry and 1H NMR Spectroscopy During Curing of Epoxy-Amine Resins, Polymer Testing, 25(7): 912-922.

Gersifi, K.E.L. , Destais-Orvoën , N. and Tersac, G. (2003). Glycolysis of Epoxid-Amine Hardened Networks. 1. Diglycidylether/Aliphatic Amines Model Networks , Polymer, 44(14): 3795-3801.

10.

Mimura, K. , Ito, H. and Fujioka, H. ( 2001). Toughening of Epoxy Resin Modified with in situ Polymerized Thermoplastic Polymers, Polymer, 42(22): 9223-9233.

11.

Merrit, M.E. , Heux, L. , Halary, J.L. and Schaefer, J. ( 1997). Determination of the Extent of Reaction of Amine Cross-Linked Epoxy Resins by Solid-State C13 and N15 NMR, Macromolecules , 30(22): 6760-6763.

12.

Barie Jr, W.P. and Franke, N.W. (1969). High-Temperature Epoxy Resins Based on 3,3,4,4-Benzophenoeteracarboxyic Dianhydride (BTDA), I&EC Product Research and Development, 1(3): 72-76.

13.

Wattsa, J.F. , Abela, M.-L. , Perruchota, C. , Loweb, C. , Maxted, J.T. and White, R.G. ( 2001). Segregation and Crosslinking in Urea Formaldehyde/Epoxy Resins: A Study by High-resolution XPS, Journal of Electron Spectroscopy and Related Phenomena, 121(1-3): 233-247.

14.

Huang, M.L. and Williams, J.G. (1994). Mechanisms of Solidification of Epoxy-Amine Resins During Cure, Macromolecules, 27: 7423-7428.

15.

Elizabeth S. Lo. , (1960). An Epoxy Resin from Phenolphthalein, Ind. Eng. Chem. 52(4): 319-321.

16.

Bader, M.G. , Bailey, J.E. and Bell, I. (1973). The Effect of Fiber-Matrix Interface Strength on the Impact and Fracture Properties of Carbon-fiber Reinforced Epoxy Resin Composites, J. Phys D: Appl. Phys., 6: 572-586.

17.

Ju, M.-Y. and Chang, F.-G. (1999). Polymer Blends of PET-PS Compatibility, J. Appl. Polym. Sci., 73(10): 2029-2040.

18.

Soldatos, A.C. and Burhans, A.S. (1970). Cycloaliphatic Epoxy Resins with Iimproved Strength and Impact Coupled with High Heat Distortion Temperature, Ind. Eng. Chem. Prod. Res. Develop., 9(3): 296-300.

19.

Lin, J.-J. , Lin, S.-F. , Kuo, T.-T. , Chang, F.-C. and Tseng, F.-P. (2000). Synthesis and Epoxy Curing of Mannich Bases Derived from Bisphenol A and Poly (oxyalkylene) diamine , J. Appl. Polym. Sci., 78(3): 615-623.

20.

Wang, M.S. and Thomas J.P. ( 1994). Polymer Nanocomposites Formed from Acidic Derivatives of Montmorillonite and an Epoxy Resins, Chem. Mater., 6: 468-474.

21.

Vanaja, R.M. V.G.K. Rao (2002). Synthesis and Characterization of Epoxy-Novolac/Bismaleimide Networks, Eur. Polym. J., 38(1): 187-193.

22.

Su Chen, Yuan Tian, Lichen , and Ting Hu (2006). Epoxy Resin/Poly Urethane Hybrid Networks Synthesized by Frontal Polymerization, Chem. Mater., 18(8): 2159-2163.

23.

Tieke, B. and Zahir, S.A. ( 1993). Anew Cross-linkable Palladium (0) Complex and its Use for Electroless Metalization of epoxy Resins, Chem. Mater. , 5: 891-897.

24.

Levchik, S.V. , Camino, G. , Luda, M.P. , Costa, L. , Costes, B. , Henry, Y. , Muller, G. and Morel, E. (1995). Mechanistic Study of Thermal Behavior and Combustion Performance of Epoxy Resins 11 GDDM/DDS System , Polymer Degradation and Stability, 48(3): 359-370.

25.

Ambrogi, V. , Giamberini, M. , Cerruti, P. , Pucci, P. , Menna, N. , Mascolo, R. and Carfgne, C. (2005). Liquid Crystalline Elastomers Based on Diglycidyl Terminated Rigid Monomers and Aliphatic Acids Part 1 Synthesis and Characterization, Polymer, 46(7): 2105-2121.

26.

Merritt, M.E. , Goetz, J.M. , Chang-Po, D.W. , Chang, P. , Heux, L. and Louis, J. (1998). Location of the Antiplasticizer in Cross-linked Epoxy Resins by 2H,15N, and 13C Redor NMR, Macromolecules, 31(4): 1214-1220.

27.

Jansen, B.J.P. , Tamminga, K.Y. , Meijer, H.E.H. and Lemstra , P.J. (1999). Preparation of Thermoset Rubbery Epoxy Resins, Polymer, 40: 5601-5607.

28.

Lauprêtre, F.C. , Eustache, R.-P. and Monnerie , L. (1995). High-Resolution Solid-state 13C Nuclear Magnetic Resonance Investigation of Local Motion in Model Epoxy Resins, Polymer, 36(2): 267-274.

29.

Athawale A.A. and Mohammed H.M. Alhousami. (2008). Novel Epoxy Resin Networks with High Impact Strength and Hardness, Journal of Reinforced Plastics and Composites, 27(6): 605-612.