The impact of replacing three polyether polyols with different levels of a single palm olein‐based natural oil polyol (NOP) was systematically correlated with the changes in foaming reactivity, cell structure, physico‐mechanical properties, and morphology of viscoelastic (VE) foams. The data show that replacing the polyether polyols with the NOP slightly increased the rate of the foaming reactivity. Increasing the NOP content resulted in increased cell size and cells remained fully open. Increased NOP content contributed to higher load bearing properties of VE foam, which can be attributed to higher functionality of NOP compared to polyether polyols. Addition of the NOP slightly increased the resilience of the foams, however, the hysteresis which is the measure of energy absorption remained mostly unaffected. Age properties, characterized by dry and humid compression sets, were mostly unaffected by the replacement of the polyether polyol with the NOP. The addition of NOP did not impact the morphology of the VE foam polymer matrix, which appears to retain a low degree of hard and soft segment domain separation. Overall, the results demonstrate a feasibility that the NOP can be used to partially replace the polyether polyols in VE polyurethane foams without significant impact on the functional performance.
Acetalization of glycerol with acetone (1 : 5) at 60 °C catalyzed by A‐46 (10 wt %) under nitrogen (N2) afforded 63 % solketal 1 a in just 15 min. Subsequently, acetalization of glycerol and bio‐based aldehydes i. e. acetaldehyde, isobutyraldehyde, n‐heptaldehyde, p‐anisaldehyde and benzaldehyde were investigated under optimized reaction conditions. The conversion and selectivity of this reaction was found to be affected by structure of aldehydes employed. Excellent conversion of 97 and 99 % were obtained using acetaldehyde and isobutyraldehyde, respectively while longer chain or aromatic aldehyde gave poor conversion between 17 and 36 %. Aldehyde with branching or aromatic ring gave better selectivity towards 6‐membered ring acetal b at the expense of conversion: p‐anisaldehyde > benzaldehyde>isobutyraldehyde>acetaldehyde>n‐heptaldehyde. Conversely, organic solvent gave adverse effects to both conversion and selectivity towards b. Optimized acetalization of glycerol/benzaldehyde was also studied. A‐46 has shown excellent stability and reactivity with no significant loss of catalytic activity in 10 subsequent runs.
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