Abstract.A new bio-based elastomer, poly(butylene 2,5-furandicarboxylate-ε-caprolactone) (PBFCL), has been synthesized from 2,5-furandicarboxylic acid, 1,4-butanediol, and ε-caprolactone successfully for the first time. The obtained copolyester was characterized in terms of chemical structure, thermal and mechanical properties, and enzymatic degradability. In PBFCL elastomer, butylene-2,5-furandiacrboxylate units (hard segments) crystallize to serve as physical crosslinks while ε-caprolactone polyester diol (soft segments) provide flexibility. PBFCL is a multi-blocked copolyester with randomly distributed rigid and soft segments. It possesses original feature of high strength and biodegradability stemming from the uses of aromatic and aliphatic monomers respectively. An important aspect of this new furanic-aliphatic polyester is its tailor-made properties simply achieved by changing the content of hard or soft segments. Typically, PBFCL-40 of optimal composition has Young's modulus as low as 15.4 MPa, tensile strength as high 24.8 MPa, and elongation as long as 885%.

Abstract. The high cost and less variety of raw materials has greatly restricted the wide application of selective laser sintering (SLS) technology. In order to make the material cheaper and more diverse, PA6 is the most preferable material. In this work, a new PA6/SiO 2 composite microsphere used for SLS was designed and fabricated. To construct the material, PA6 porous microspheres with diameters of 20-80 µm and a certain pore volume were firstly prepared by the dissolution precipitation method. Then, SiO 2 was generated in situ in the PA6 porous microsphere framework, thus achieving a special structured PA6/SiO 2 composite microsphere. These microspheres with much well dispersed SiO 2 in PA6 matrices formed a powder with high bulk density and good electron conductivity. The particle size and weight fraction of the two components can be well controlled by adjusting the experimental conditions. Differential scanning calorimetry (DSC) data showed that the composite powder had a larger sintering window, which would be beneficial for SLS processing. The introduction of SiO 2 reduced the rate of water absorption in the composite powder, which could improve the accuracy of SLS forming. This work has certain significance as a reference for the design and development of SLS polymer-based composite materials.