3D-printed poly(L-lactic acid) Haversian bone scaffold with microspherulitic surface and biocompatibilities.

This work proposes a facile fabrication strategy of poly(-lactic acid) haversian bone scaffold with micro-spherulitic surface, designed by combination of the fused deposition modeling (FDM) 3D printing and homo-epithelial crystallization (EC). Further long chain branched modification of PLLA scaffold was carried out by a two-step ring-opening reaction of pyromellitic dianhydride (PMDA) and 1,3-phenylene-bis-oxazoline (1,3-PBO) to control the deformation stability and crystallization of PLLA. The influence of concentric circular gaps and the extrusion rate on the morphology of PLLA haversian bone scaffold was investigated and optimized.

Preparation and properties of polydimethylsiloxane-regulated oriented microporous poly (-lactic acid) biomimetic bone repair materials.

Despite the exceptional biocompatibility and degradability of Poly (-lactic acid) (PLLA), its brittleness, low melting strength, and poor bone induction makes it challenging to utilize for bone repair. This study used a simple, efficient solid hot drawing (SHD) method to produce high-strength PLLA, using supercritical CO (SC-CO) foaming technology to give PLLA a bionic microporous structure to enhance its toughness, while precisely controlling micropore homogeneity and improving the melt strength by using Polydimethylsiloxane (PDMS). This PDMS-regulated oriented microporous structure resembled that of natural bone, displaying a maximum tensile strength of 165.

Bionic structure and biocompatibilities of long chain branched poly(L-lactic acid) oriented microcellular foaming material.

In order to solve the problem of uneven microporous structure of Poly(L-lactic acid) (PLLA) bulk orientation by using biological safety multi-functional plant oil as chain extenders (CE), multi-armed flexible chains were introduced into PLLA through reactive processing to prepare long chain branched PLLA (LCB-PLLA). When the total content of the CE was 6.15 wt%, PLLA and the CE reacted most fully, while maintaining the tensile strength of PLLA and improving toughness.

Bionic structure and blood compatibility of highly oriented homo-epitaxially crystallized poly(l-lactic acid).

A highly oriented poly(l-lactic acid) (PLLA), with a blood vessel-like biomimetic structure, was fabricated using solid-phase hot drawing technology and homo-epitaxial crystallization to improve the mechanical properties and biocompatibility of PLLA. Long chain branched PLLA (LCB-PLLA) was prepared through a two-step ring-opening reaction, and a consequent draw as high as 1000 % was achieved during the hot drawing. The modulus and tensile strength were found to have increased through the formation of oriented shish-kebab like crystals along the drawing direction during processing.

Preparation and properties of oriented microcellular Poly(l-lactic acid) foaming material.

Poly(l-lactic acid) (PLLA) displays simultaneous repair and regeneration properties. Therefore, it is vital for developing bone repair materials while improving their mechanical strength, and biocompatibility is essential for guaranteeing its application. In this manuscript, using solid hot drawing (SHD) technology to fabricate an oriented shish-kebab like structure, furthermore, the interface-oriented grain boundary controlled the nucleation site and cell morphology during low temperature supercritical carbon dioxide (SC-CO) foaming process, resulted in an oriented microcellular structure which was similar to load-bearing bone.