Effect of castor oil/polycaprolactone hybrid polyols on the properties of biopolyurethane

Abstract

Organic solvent soluble castor oil/polycaprolactone diol (PCL) based polyurethane for artificial leather was prepared by a one-step polymerization with 4,4'-diphenylmethane diisocyanate (MDI) at different castor oil contents. The PCL and MDI acted as soft and hard segments, respectively, and the castor oil acted as a dendritic point in the castor oil/PCL based polyurethane structure. The tensile properties and shape memory of castor oil/PCL based polyurethane were enhanced remarkably, compared with the PCL based polyurethane because of the increased hard segment portion and crosslinking density by the three urethane bonds formed per molecule in the castor oil/PCL mixed system. The dynamic mechanical analysis showed that the storage modulus of castor oil/PCL based polyurethanes increased with increasing castor oil content. In the enzymatic degradation test, castor oil/PCL based polyurethane degraded faster than conventional petroleum based polyurethane. This research suggests the potential to use the castor oil/PCL based polyurethane as a biobased coating materials.

Castor oil‐based polyols with gradually increasing functionalities for biopolyurethane synthesis

“…Castor oil is obtained from seeds of Ricinus communis comprising mainly of recinoleic acid (12‐hydroxy‐ cis ‐9‐octadecenoic acid) in its triglyceride structure . Having inherent hydroxyl functionalities in its triglyceride structure castor oil can be easily utilized as polyols in the preparation of PUs without any modification to its original structure . It is also a nonedible and cost‐efficient plant oil, making it an ideal alternative to petroleum‐based polyols.…”

Rational design of sustainable polyurethanes from castor oil: towards simultaneous reinforcement and toughening

“…For example, the tensile strength and Young's modulus of the polyurethane prepared from CO and hexamethylene diisocyanate are only 0.8 and 3.59 MPa, respectively, meanwhile the elongation at break is 31.6% [11]. Some studies have combined polymeric diols such as poly (ethylene glycol) and poly(ε-caprolactone) with castor oil to prepare polyurethanes [30,31]. Such a technique is useful to improve the toughness of CO-based polyurethanes.…”

Fabrication of castor‐oil/polycaprolactone based bio‐polyurethane foam reinforced with nanocellulose

“…Furthermore, the relatively hard segment portion of MDI is increased with increasing CO content because the soft segment portion was decreased by CO, which has a lower molecular weight than PCL, resulting in an increase in T g . The amplitude of tan δ decreased remarkably with CO content, which indicates an abundant crosslinking formation because of CO .…”

“…The thermal decomposition parameters such as the initial decomposition temperature ( T id ) and thermal decomposition temperature at the maximum rate ( T dm ) to determine thermal stability are summarized in Table . The degradation of the COPU foams takes place in the range of 340–570°C in two steps: the first between 340 and 400°C corresponds to the urethane decomposition; the second between 510 and 560°C corresponds to the degradation of urea bonding decomposition . In the first decomposition stage, the fastest rate of loss was at 349°C for unmodified CO20PU foam, and 394°C for nanocellulose‐reinforced CO30PU foam.…”