Influence of Castor Oil-Based Polyurethane on Physico-Chemical Properties of Calcium Silicate Cement
Eduardo R. Magdaluyo, Jr., Clodualdo M. Aranas, Jr., and Jovilyn D. Masiglat
Department of Mining, Metallurgical and Materials Engineering
University of the Philippines, 1101 Diliman, Quezon City, Philippines
corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it. / This email address is being protected from spambots. You need JavaScript enabled to view it.
ABSTRACT
Polyurethane from castor oil and toluene diisocyanate was activated in the presence of calcium silicate cement paste, with varying equivalent free isocyanate (NCO) to equivalent free hydroxyl (OH) moiety and cement to water ratio. It was shown that as the NCO/OH ratio and percent cement mixture were increased, the compressive strength and bulk density of the obtained polymer-modified calcium silicate cement materials improved significantly. The increase in the strength and density is explained by low porosity and the presence of polyurethane hard segments in the polymer structure. Moreover, the powder x-ray diffraction and surface morphology investigations of the castor oil-based polyurethane-reinforced cement composites revealed the interpenetration of the polymer macromolecules in the cementitious matrix. The Ca2+ from the portlandite phase was readily available to react with the hydroxyl groups from the polyurethane macromolecule and excess monomer resulting in calcium oxide-terminated diisocyanate.
INTRODUCTION
One of the most widely used construction materials includes conventional cement and concrete. The materials have low flexural strength and failure strain as well as susceptible to chemical damage in spite of their good physical properties and relatively low cost. This problem can be solved by fabricating composite material wherein an organic polymer is added to the inorganic cement powder. The two different phases are continuously interpenetrated and can be optimized for producing lightweight components with interesting potential applications in the field of non-structural and construction materials . . . . . . . . .
REFERENCES
CHUNG D. 2004. Review use of polymers for cementbased structural materials. J Mater Sci 39(9): 2973-78.
CLARO NETO S. 1997. Caracterizações físico-químicas de um poliuretano derivado de óleo de mamona utilizado para implantes ósseos. [PhD thesis]. São Paulo: Instituto de Química de São Carlos, University of São Paulo. 127p.
DALGLEISH B, PRATT P, TOULSON E. 1982. Fractographic studies of microstructural development in hydrated portland cement. J Mater Sci 17(8): 2199-07.
HEPBURN C. 1992. Trends in polyurethane elastomer technology. Iran J Polym Sci Technol 1(2): 84-110.
HERRINGTON R, HOCK K. 1998. Flexible polyurethane foams, 2nd ed. Midland, Michigan: Dow Chemical Company.
ISMAIL M, ALI M, EL-MILLIGY A, AFIFI M. 1998. Physico-chemical studies of gamma-irradiated polyester-impregnated cement mortar composite. J Radioanal Nucl Chem 238(1-2): 111-117.
JAWED I, SKALNY J, YOUNG J. 1983. Structure and performance of cements. London: Applied Science Publishers. p. 237-312.
KHATU S, HSIEH Y. 1997. Chlorine degradation of polyether-based polyurethane. J Polym Sci A: Polym Chem 35(15): 3263-73.
MYTHILI C, RETNA M, GOPALAKRISHNAN S. 2004. Synthesis, mechanical, thermal and chemical properties of polyurethanes based on cardanol. Bull Mater Sci 27(3): 235-241.
ODLER I, LIANG N. 2003. Properties and development of the microstructure in cement pastes modified by a styrene-butadiene co-polymer. Adv Cem Res 15(1): 1-8.
OERTEL G. 1994. Polyurethane Handbook. Berlin: Hanser Gardner Publications. 688p.
RASTOUL K, VAN DAMME H, LAFUMA F, LEQUEUX F, COLOMBET P, MANSOUTRE S, PASQUIER M. 2003. A rheological study of associating polymerparticle interactions in tricalcium silicate pastes. Polym Int 52(4): 633-637.
SINGH N, RAI S. 2001. Effect of polyvinyl alcohol on the hydration of cement with rice husk ash. Cement Concrete Res 31(2): 239-243.
SUJJAVANICH S, LUNDY J. 1998. Development of strength and fracture properties of styrene-butadiene copolymer latex-modified concrete. ACI Mater J 95(2): 131-143.
TAYLOR H. 1997. Cement Chemistry, 2nd ed. London: Thomas Telford Publishing. 459p.
VERDOLOTTI L, DI MAIO E, LAVORGNA M, IANNACE S, NICOLAIS L. 2008. Polyurethane cement-based foams:characterization and potential uses. J Appl Polym Sci 107(1): 1-8.
YANG Z, ZHAO B, QIN S, HU Z, JIN Z, WANG J. 2004. Study on the mechanical properties of hybrid reinforced rigid polyurethane composite foam. J Appl Polym Sci 92(3): 1493-1500.
ZHONG S, CHEN Z. 2002. Properties of latex blends and its modified cement mortars. Cement Concrete Res 32(10): 1515-24.
