Novel Multiblock Poly(ε-caprolactone) Copolyesters Containing D-Glucose Derivatives with Different Bicyclic Structures

Abstract

For improving the thermal stability, glass transition temperature (T g ), stiffness, and hydrophilicity of poly(ε-caprolactone) (PCL), two glucose-based bicyclic rigid structures, namely 1,4:3,6-dianhydrohexitols-Dglucidol (isosorbide, Is) and dimethyl 2,4:3,5-di-O-methylene-D-glucarate (glu-diester) have been introduced into PCL via chain extension. The two series of multiblock copolyesters obtained, PCL-b-PIS and PCL-b-PBG, have high number-average molecular weights in the range of 9.6 × 10 4 to 12.4 × 10 4 g mol −1 and small PDI values. The thermal and crystallization behaviors, hydrophilicity, as well as the mechanical properties of PCL-b-PIS and PCL-b-PBG have been well investigated. In comparison, the improved effect on thermal stability and T g of PCL is more pronounced for PCL-b-PBG than for PCL-b-PIS. Both glucose-based units retard the crystallinity of PCL. However, the crystal structure and melting temperature of PCL remain unchanged. The rigidness of PCL is enhanced when glucose-based bicyclic units are introduced as reflected by the increasing storage modulus over all of the studied temperatures. The mechanical properties of PCL-b-PIS are better than those of PCL-b-PBG, especially for the samples containing 30 wt % sugar units. This can be due to the good compatibility of PIS with the PCL block. Although both Is and glu-diester enhance the hydrophilicity of PCL, the PCL-b-PBG copolyester always shows higher hydrophilicity than that of PCL-b-PIS in the whole composition.

Ecofriendly Preparation and Characterization of a Cassava Starch/Polybutylene Adipate Terephthalate Film

“…The application of biodegradable packaging has gradually become a trend. In addition, researchers have used low-cost natural degradable materials for blending with biodegradable polymers to prepare composite materials and achieve certain results [1][2][3][4].…”

Unsaturated Poly(ester-urethanes) with Stereochemically Dependent Thermomechanical Properties

“…Use of conformationally-locked rigid-rings, such as isohexides or cyclohexylene has been harnessed to create polyesters and polyurethanes through scalable polycondensation routes. [13][14][15][16][17][18] While incorporation of these groups results in stereochemicallydependent thermomechanical properties, the molecular weights of the resultant polymers are generally modest (Mw < 100 kDa), thus limiting their mechanical properties.…”

“…The presence of cis/trans stereoisomerism in both ring systems and double bonds has been used to create polymers in which the thermomechanical properties are controlled by the stereochemistry of the monomer unit. Use of conformationally locked rigid-rings, such as isohexides or cyclohexylene, has been harnessed to create polyesters and polyurethanes through scalable polycondensation routes. − While incorporation of these groups results in stereochemically dependent thermomechanical properties, the molecular weights of the resultant polymers are generally modest ( M w < 100 kDa), thus limiting their mechanical properties.…”

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

“…Isosorbide [33][34][35], a commercially available compound with double aliphatic rings, may be the good modifier for castor oilbased polyurethane. Besides the stiff nature, the hydroxyl of isosorbide is also secondary hydroxyl group, and thus has comparable activity with castor oil when reacting with diisocyanate.…”