Glutaraldehyde as Ambient Temperature Crosslinking Agent of Latex Films from Natural Rubber Grafted with Poly(diacetone acrylamide)
- 145 Downloads
The concept of using glutaraldehyde (GTA) to crosslink natural rubber (NR) particles bearing diacetone acrylamide (DAAM) functional groups during film formation was investigated in the present work. The primary advantage of this curing system is that it is feasible under ambient conditions, which can lower operating costs of the curing process. Graft copolymers of NR and poly(diacetone acrylamide) prepared with 5 wt% of DAAM (NR–g–PDAAM5) were synthesized by seeded emulsion polymerization at 50 °C. Then, the tensile properties were measured for cast films formed from NR–g–PDAAM5 latex in the absence and presence of GTA. The results revealed increased tensile strength of the NR–g–PDAAM5 film, when GTA was added into the latex prior to film casting. The crosslinking of NR–g–PDAAM5 latex film by reaction with GTA, after film casting, was also investigated using attenuated total reflection Fourier transform infrared (ATR–FTIR) and dynamic mechanical thermal analysis (DMTA). ATR–FTIR analysis demonstrated that crosslinking reactions formed conjugated C=C double bonds between the active carbonyl groups of DAAM and GTA. The complementary use of DMTA also corroborated that crosslinking reactions took place involving the grafted PDAAM chains on the NR particles. This was evidenced by a clear shift towards higher temperatures of the tan δ peak, corresponding to the Tg of NR–g–PDAAM phase, when GTA was incorporated into the NR–g–PDAAM5 latex before film formation. Additionally, a noticeable increase in thermal stability of the NR–g–PDAAM5 film was also observed with added GTA. Hence, it can be concluded that GTA is an efficient room-temperature crosslinker for NR particles functionalized with DAAM. This curing system can also be considered an alternative, simple, and inexpensive method for curing NR latex compounds, as only one component (GTA) is required in the curing process.
KeywordsGraft copolymers Natural rubber Diacetone acrylamide Glutaraldehyde
This work was supported by the Research Fund of Prince of Songkla University, SAT581267S. The authors would like to thank the Research and Development Office (RDO) and Assoc. Prof. Seppo Karrila for editing this article.
- 4.Tale NV, Jagtap RN (2010) Iran Polym J 19:801Google Scholar
- 17.Pye DJ (1960) Polymer composition and method. US Patent 2,960,486Google Scholar
- 18.Zweigle ML (1973) Removal of monomer from acrylamide polymers with sulfur dioxide. US Patent 3,780,006Google Scholar
- 29.Eng AH, Ong EL (2001) In: Bhowmick AK, S Howard (ed) Handbook of elastomers, 2nd edn. Marcel Dekker, Inc., New York, pp 29–60Google Scholar
- 31.Honeycutt T, Flowery B (2005) Decreasing allergenicity of natural latex rubber prior to vulcanization. US Patent 20050277722 A1Google Scholar
- 32.Honeycutt T (2006) Decreasing allergenicity of natural latex rubber prior to vulcanization. US Patent 7056970 B2Google Scholar
- 33.Honeycutt T, William D, Matthew C, Russell C, Mark S (2007) Rubber World 237:32Google Scholar
- 34.Honeycutt T, Sharivker V, Sharivker S, Blinov V, Doyle W (2005) In international latex conference papers, CharlotteGoogle Scholar
- 36.Smith MB (2015) Organic chemistry: an acid–base approach, 2nd edn. CRC Press, Boca RatonGoogle Scholar
- 39.Hutchinson JM (1997) In: Haward RN, Young RJ (eds) The physics of glassy polymers, 2nd edn. Springer, London, pp 128–138Google Scholar
- 47.Kim W, Kim SD, Lee SB, Hong IN (2000) J Ind Eng Chem 6:348Google Scholar