An
efficient scheme for the synthesis of 1,1-cyclopentylenylbisphenol
(bisphenol CP) has been developed starting from dicyclopentadiene,
a C5 byproduct from the petroleum cracking process. The synthetic
steps leading to bisphenol CP consist of mostly isomerization and
addition reactions, which are higher in their atom-economy efficiencies
than those based upon condensation reactions. In addition, alkoxylation
by cyclic carbonates converted bisphenol CP into ethoxylated and propoxylated
ether diols. The transformation of hydroxyl functional groups from
bisphenols to alkoxylated alcohols increased the reactivity of their
hydroxyl groups toward isocyanates, as evidenced by achieving >3
times
higher molecular weights of the segmented polyurethanes (PUs) in GPC
analysis using alkoxylated diols as chain extenders instead of bisphenols.
In addition, the incorporation of five-membered cardo-type groups
onto the PU side chains through alkoxyl diols of bisphenol CP also
significantly enhances the phase mixing of the resulting hard and
soft segments, leading to a series of robust PUs.