This study examines the impact of varying isocyanate indices on the morphology and properties of bio-based viscoelastic polyurethane (VE PU) foams produced using high-pressure processing and moulding technology. Palm-based polyol, referred to herein as Pioneer E-135, was used as a sustainable alternative to petroleum-based polyol. VE PU foams were formulated with different isocyanate indices (71%, 75%, 79% and 83%) and their physical, mechanical and morphological characteristics were evaluated. Results indicated that the VE PU foam containing 10% Pioneer-E135 polyol and an isocyanate index of 83% exhibited superior mechanical properties compared to the VE PU foam with 100% petroleum-based polyol. The incorporation of 10% Pioneer-E135 polyol significantly enhanced the mechanical properties, including surface texture, morphology and load-bearing capacity, as indicated by indentation force deflection and sag factor measurements. Higher NCO indices contributed to increased tensile strength, tear strength, and ageing resistance, but resulted in lower density and reduced elongation at break. Overall, the optimised processing parameters enabled the successful production of high-quality, bio-based VE PU foams using high-pressure machine technology.
Abdul-RaniAMHopkinsonNDickensPM. Effect of mold temperature on high-resilience cold-cure flexible polyurethane foam surface texture. J Cell Plast2005; 41: 133–151. https://doi.org/10.1177/0021955X05051738
4.
SmiecinskiTMNeffRA. Visco-elastic polyurethane foam: the impact of isocyanate upon foam morphology. In: Proceedings of the API Polyurethanes 2006 Technical Conference, Salt Lake City, UT, 25–27 September 2006, p. 405.
5.
WhiteL.Viscoelastic foam mattresses: marketing hype or molecular miracle?Urethanes Technol2006; 18(6): 22-27. https://goliathecnext.com. Available from. (accessed 27 December 2017).
FlôresCCRufinoTCNahraLR, et al. Viscoelastic polyurethane foams from unmodified kraft lignin dispersed into methoxy polyethylene glycol and palm kernel oil as partial substitutes of petroleum-based polyols. Research Square. 2022. https://doi.org/10.21203/rs.3.rs-1171841/v1
8.
ZhangDChenS. The study of palm-oil-based bio-polyol on the morphology, acoustic and mechanical properties of flexible polyurethane foams. Polym Int2019; 69: 257–264. https://doi.org/10.1002/pi.5941
9.
ChengYXuZChenS, et al.The influence of closed pore ratio on sound absorption of plant-based polyurethane foam using control unit model. Appl Acoust2021; 180: 108083. https://doi.org/10.1016/j.apacoust.2021.108083
10.
RajanKPDhiliprajBDManikandanR, et al.Preparation of moulded viscoelastic polyurethane foam for pillow application. Cell Polym2011; 30(1): 13–16. https://doi.org/10.1177/026248931103000102
11.
WęgrzykGGrzędaDRyszkowskaJ. The effect of mixing pressure in a high-pressure machine on morphological and physical properties of free-rising rigid polyurethane foams—a case study. Materials2023; 16: 857. https://doi.org/10.3390/ma16020857
12.
AtikaAMustafaAG. Investigating the recent development of bio-based polyurethane foam produced from renewable resources. In: JawaidMThariqMSabaN (eds). Fibre composites Singapore: Springer, 2021, pp. 299–316. DOI: 10.1007/978-981-33-4749-6_12.
13.
SinghAPBhattacharyaM. Viscoelastic changes and cell opening of reacting polyurethane foams from soy oil. Polym Eng Sci2004; 44(10): 1977–1986. https://doi.org/10.1002/pen.20201
14.
VaughanBRWilkesGLDounisDV, et al.Effect of vegetable-based polyols in unimodal glass-transition polyurethane slabstock viscoelastic foams and some guidance for the control of their structure–property behavior. II. J Appl Polym Sci2011; 119: 2698–2713. https://doi.org/10.1002/app.32864
15.
SilvaVRDMosiewickiMAYoshidaMI, et al.Polyurethane foams based on modified tung oil and reinforced with rice husk ash II: mechanical characterization. Polym Testing2013; 32: 665–672. DOI: 10.1016/j.polymertesting.2013.03.010.
16.
Nurul`AHTuan Noor MazneeTIMohdNS, et al.Viscoelastic foams having high dissipation energy. US Patent2019; 10: 202. 482 B2.
17.
KlempnerDSendijarevicV. Fundamentals of foam formation. In: KlempnerDSendijarevicV (eds). Handbook of polymeric foams and foam technology: Hanser, 2014, pp. 5–15.
18.
SulemanSKhanSMGullN, et al.A comprehensive short review on polyurethane foam. Int J Innov Sci Res2014; 12: 165–169.
19.
SungHKByungK. Effect of isocyanate index on the properties of rigid polyurethane foams blown by HFC. Macromol Res2018; 16(5): 467–472. DOI: 10.1007/bf03218546.
20.
NurulAHKosheela DeviPPTuan Noor MazneeTI, et al.Effect of methylene diphenyl diisocyanate index on physico-mechanical and morphological properties of palm olein-based viscoelastic polyurethane foams. J Oil Palm Res2022; 35(2): 236–246. DOI: 10.21894/jopr.2022.0023.
21.
ASTM International. ASTM D3574-03: standard test methods for flexible cellular materials—slab, bonded and molded urethane foams: ASTM International, 2003.
22.
LeeCSOoiTLChuahCH, et al.Effect of isocyanate index on physical properties of flexible polyurethane foams. Malays J Sci2007; 26: 91–98.
23.
IvdreAAbolisASevastyanovaI, et al.Rigid polyurethane foams with various isocyanate indices based on polyols from rapeseed oil and waste PET. Polymers2020; 12: 738. https://doi.org/10.3390/polym12040738
24.
SrihanumATuan Noor MazneeTIKosheela DeviPP, et al.Low density rigid polyurethane foam incorporated with renewable polyol as sustainable thermal insulation material. J Cell Plast2022; 58(3): 485–503. https://doi.org/10.1177/0021955X211062630
25.
RojekAProciakA. Effect of different rapeseed oil-based polyols on mechanical properties of flexible polyurethane foams. J Appl Polym Sci2012; 125(4): 2936–2945. https://doi.org/10.1002/app.36500
26.
SulemanSKhanSMGullN, et al.Synthesis and characterization of visco-elastic polyurethane foams. Int J Innov Appl Stud2019; 9(4): 1878–1886.
27.
ProciakAMalewskaEBakS. Influence of isocyanate index on selected properties of flexible polyurethane foams modified with various bio-components. J Renew Mater2016; 4(1): 78–85. https://doi.org/10.7569/JRM.2015.634129
28.
LiZLiuJXieX. Polyurethane foams co-blown by water and alkylated polyethylenimine-CO2 adducts: an additive or antagonistic effect. J Cell Plast2023; 59(5–6): 361–377. https://doi.org/10.1177/0021955X231177805
29.
Mohd HaziqDRohahAMSitiKG, et al.Fumed nanosilica as filler for semi-rigid palm oil-based polyurethane foam: mechanical, material, thermal, and fire response. Cell Polym2024; 43(1): 3–16.
30.
ZhangJWuSWangF, et al.Luffa seed oil-modified polyurethane viscoelastic foam with good tear resistance. Ind Crops Prod2023; 193: 116156. https://doi.org/10.1016/j.indcrop.2022.116156
31.
HojabriLKongXNarineSS. Novel long chain unsaturated diisocyanate from fatty acid: synthesis, characterization and application in bio-based polyurethane. J Polym Sci A Polym Chem2010; 48: 3302–3310. https://doi.org/10.1002/pola.24114
32.
Tuan Noor MazneeTINor AzowaIPoo PamKD, et al.Improved dynamic properties of thermoplastic polyurethanes made from co-monomeric polyester polyol soft segments based on azelaic acid. J Appl Polym Sci2021; 138: 50815. https://doi.org/10.1002/app.50815
33.
TereshatovVVMakarovaMASenichevVY, et al.The role of the soft phase in the hardening effect and the rate dependence of the ultimate physico-mechanical properties of urethane-containing segmented elastomers. Colloid Polym Sci2015; 293: 153–164. https://doi.org/10.1007/s00396-014-3395-5
