The calorimetric study in the 13·8–340°K range of δ-valerolactone, its polymer, and of the δ-valerolactone polymerization

Syntheses, characterization, and hydrolytic degradation of P(ε‐caprolactone‐co‐δ‐valerolactone) copolymers: Influence of molecular weight

“…The values of the degree of crystallinity of the samples ( X c ) can be calculated from the latent heat of fusion of the copolymers divided by the reported enthalpies of 100% crystalline polymer . The most commonly used values, considered here for calculations, are close to 136.1 and 181.8 J/g for PCL and PVL, respectively . Table shows clearly that crystallinity rate increased with molecular weight.…”

Polyurethanes based on lignin-derived metabolic intermediate with strong adhesion to metals

“…27 Bis(2-hydroxyethyl) 2-oxo-2 H -pyran-4,6-dicarboxylate (BHPDC) was synthesized according to previous report. 44…”

“…27 Bis(2-hydroxyethyl) 2-oxo-2H-pyran-4,6-dicarboxylate (BHPDC) was synthesized according to previous report. 44 Nuclear magnetic resonance ( 1 H NMR and 13 C NMR) spectra were obtained on a JEOL model 400YH or AL300 spectrometer at room temperature. All chemical shifts were reported in parts per million (ppm) downfield from SiMe 4 .…”

Isohexide hydroxy esters: synthesis and application of a new class of biobased AB-type building blocks

“…30 J g À1 , the absence of a melting endotherm in the second heating run (as well as (cold) crystallization) indicates a low rate of crystallization for this polymer. Nevertheless, the T g enhancing effect of the bicyclic isohexide skeleton is evident by comparison with the conformationally unrestricted analogue poly-d-valerolactone, which results in an increase of T g of 81-86 C. 12 Even more surprising than the low T g s of PE-1 and PE-2 is the T g value of 80 C recorded for co-polyester PE-5, which is fully in line with the results of Wu et al Also the observation of a melting endotherm (rst run only, very low melting enthalpy) is unexpected since a high degree of incorporation of monomer (5c) in PE-5 is expected to result in a stereoirregular, and hence amorphous polymer. The observed low T g for PE-6 is in line with that of homopolyester PE-1.…”