The epoxidation of natural rubber using hydrogen peroxide and formic acid is perturbed by the presence of adventitious iron(II), due to the interference of chemistry associated with Fenton's Reagent and the facile generation of hydroxyl radicals. The extent of intervention is dependent on the concentration of iron(II) and can result in retardation of the rate of epoxidation due to the depletion of hydrogen peroxide, enhanced oxidative degradation and a reduction in the gel content of the rubber. Degradation of the surfactant leads to destabilisation of the latex and premature coagulation of the polymer for iron(II) concentrations above 10 p.p.m. Fenton's Reagent may be useful as a chemical method to depolymerise polyisoprenoid latices at iron(II) concentrations above 50 p.p.m. However, vigorous gas and heat evolution and premature coagulation of the polymer can result in an uncontrollable and potentially hazardous reaction.
GellingI.R. and PorterM., Natural Rubber Science and Technology, (RobertsA.D., ed.), Chap. 10., Oxford: Oxford University Press, 1988
3.
International Standards Organisation, Rubber Latex - Centrifuged or Creamed, Ammonia-Preserved Types - Specifications. ISO 2004, 1979
4.
PendleT.D., Unpublished Data. Malaysian Rubber Producers’ Research Association, United Kingdom
5.
GellingI.R., Unpublished Data. Malaysian Rubber Producers’ Research Association, United Kingdom
6.
FarleyP.S., Unpublished Data. Malaysian Rubber Producers’ Research Association, United Kingdom, 1991
7.
FarleyP.S., Geometrical Isomerisation of Polyisoprenes. Part 1, The Occurrence and Estimation of Trans-Alkene Functionality in Natural Rubber., J. Nat. Rubb. Res., 6(4), 1991, 215
8.
International Standards Organisation, Rubber - Determination of Metal Content by Atomic Absorption Spectrometry. ISO 6101-5, 1990
NormanR.O.C. and WestP.R., Electron Spin Resonance StudiesXIX.Oxidation of Organic Radicals and the Occurrence of Chain Processes during the Reactions of Some Organic Compounds with the Hydroxyl Radical Derived from Hydrogen Peroxide and Metal Ions, J. Chem. Soc. B., 1969, 389
12.
SosnovskyG. and RawlinsonD.J., Organic Peroxides (SwernD., ed.), Vol. 2, Chap. 2. New York: Interscience, 1971
13.
RazuvaevG.A., ShushunovV.A., DodonovV.A. and BrilkinaT.G., Organis Peroxides (SwernD., ed.), Vol. 3, Chap. 1. New York: Interscience, 1972
14.
ShapilovO.D. and KostyukovskiiL., Reaction Kinetics of Hydrogen Peroxide with Formic Acid in Aqueous Solutions. Kinet. Catal. (Engl. Transl.), 15, 1975, 947
15.
CampbellD.S., The Relevance of Phase Heterogeneity in Epoxidations using Formic Acid and Hydrogen Peroxide. Proc. Int. Conf. Polym. Latex. 111. 1989, London
16.
CampbellD.S. Unpublished Data. Malaysian Rubber Producers’ Research Association, United Kingdom
BarnardD., BatemanL., CunneenJ. I. and SmithJ. F., The Chemistry and Physics of Rubber-like Substances (BatemanL., ed.), Chap. 17. London: Maclaren, 1963
19.
BamardD. andLewisP.M., Natural Rubber Science and Technology, (RobertsA.D., ed.), Chap. 13. Oxford: Oxford University Press, 1988
20.
BoonA.J., Hock Cleavage - The Cause of Main Chain Scission in Natural Rubber Autoxidation? J. Nat. Rubb. Res., 3(2), 1988, 90
21.
ChalkA.J. and SmithJ.F., Catalysis of Cyclohexene Autoxidation by Trace Metals in Non-Polar Media. Part 1. Metal Salts. Trans. Farad. Soc., 53, 1957, 1214
22.
ChalkA.J. and SmithJ.F., Catalysis of Cyclohexene Autoxidation by Trace Metals in Non-Polar Media. Part 2. Metal Salts in the Presence of Chelating Agents. Trans. Farad. Soc., 53,1957,1235
23.
MayoF.R., EggerK. and IrwinK.C., Accelerated Oxidations of Polyisoprene. 1. Metal-catalysed Oxidations in Solution. Rubb. Chem. Technol., 41, 1968, 271
24.
BevilacquaE.M., Chain Scission in the Oxidation of Hevea. 1. J. Am. Chem. Soc., 77, 1955, 5394
25.
BevilacquaE.M., Chain Scission in the Oxidation of Hevea. 11. J. Am. Chem. Soc., 77, 1955, 5396
26.
Societe Meridionale du Caoutchouc Someca, Manufacture of Plastified Rubber and Adhesive Latex. U.S. Pat. Appl. No. 2430481, 1945
27.
ShanleyE.S. and GreenspanF.P., Highly Concentrated Hydrogen Peroxide-physical and Chemical Properties. Ind. Engng Chem., 39, 1947, 1536
28.
MerzJ.H. and WatersW.A., Some Oxidations involving the Free Hydroxyl Radical. J. Chern. Soc., S15, 1949
29.
RazuvaevG.A.and Boguslavskaya, Syntheses by Means of Free Hydroxyl Radicals. 1. Oxidative Dimerization of Aliphatic Ethers and Esters. J. Gen. Chem. USSR, (Engl. Transl.), 30, 1960, 4059
30.
CottonF.A. and WilkinsonG., Advanced Inorganic Chemistry, 3rd edition, Chap. 25. New York: Interscience, 1972
31.
VogelA.I. A Text Book of Quantitative Inorganic Analysis, 3rd edition, Chap. 3. London: Longmans, 1961
32.
GreenspanF.P. and MacKellarD.G., Analysis of Aliphatic Peracids. Analyt. Chem., 20, 1948, 1061
