In this study, two different viscosity-average molecular weight (eta = 4.0 and 7.8) poly(L-lactide) (PLLA) were synthesized by ring-opening polymerization and the poly(L-lactide)/hydroxyapatite composites (PLLA/HA) were prepared by blending HA particles (size range: 25-45 microm and Ca/P = 1.69) with a content of 10, 30, and 50 wt% in PLLA solution with further evaporation of the solvent. The plain PLLA polymers and PLLA/HA composites were compression-molded and machined to yield 25 x 3 x 2 mm3 specimens. The molar mass of resulting specimens was decreased drastically due to the hydrolytic and thermal degradation of ester bonds. Scanning electron microscopy and thermal gravimetric results indicated that the compositions of HA in PLLA were well dispersed. With increasing HA content, the crystallinity of PLLA/HA composites are slightly increased due to the effect of HA as a nucleating agent. The dynamic mechanical analysis is useful in studying the viscoelastic behaviour of the PLLA/HA composites and no secondary relaxation was observed below the glass-to-rubber transition (60 degrees C). The mechanical properties of the PLLA/HA composites were found to vary with HA content. Increased levels of HA resulted in increased bending modulus and strength.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1163/156856200743904 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Co-culture bioprinting of tissue-engineered bone-periosteum biphasic complex for repairing critical-sized skull defects in rabbits.
Int J Bioprint
March 2023
Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Tissue engineering based on bioprinting technology has broad prospects in the treatment of critical-sized bone defect. Nevertheless, it is challenging to construct composite tissues or organs with structural integrity. Periosteum and stem cells are important in bone regeneration, and it has been shown that co-culture engineering system could successfully repair bone defects.
View Article and Find Full Text PDFElectrospun hydroxyapatite loaded L-polylactic acid aligned nanofibrous membrane patch for rotator cuff repair.
Int J Biol Macromol
September 2022
Beijing Key Laboratory of Advanced Functional Polymer Composites, College of Material Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address:
Rotator cuff repair remains a challenge clinically due to the high retear rate after surgical intervention. There is a significant need to develop functional biomaterials facilitating tendon-to-bone integration. In this study, hydroxyapatite (HA) incorporated polylactic acid (PLLA) aligned nanofibrous membranes were fabricated by electrospinning as a low-cost sustainable rotator cuff patch.
View Article and Find Full Text PDFInfluence of the different composites (PLA/PLLA/HA/β-TCP) contents manufactured with the use of additive laser technology on the biocompatibility.
Acta Bioeng Biomech
December 2021
Department of Laser Technology, Automation, and Production Organization, Wrocław University of Science and Technology, Wrocław, Poland.
Purpose: In recent years, it has become extremely important to search for more and more natural and biocompatible materials that allow for the reconstruction of natural tissues with as few side effects as possible. The aim of the present paper is to define mechanical properties such as compressive stress and Young's Modulus and to estimate the ability of human bone cell strains to form biofilm on bioresorbable composites manufactured of polylactide and poly-l-lactide (PLA and PLLA) and hydroxyapatite and tricalcium phosphate (HA and β-TCP) with the use of Selective Laser Sintering (SLS) method.
Methods: Microbiological tests were conducted on three variants of solid specimen made with additive laser technology.
Purpose: To use a 3D printed poly (L-lactide) acid (PLLA) and hydroxyapatite (HA) composite as a bone substitute for reconstruction of a critical bone defect in the radius of rabbits.
Methods: A 1.5 cm ostectomy was performed in the radial diaphysis of 60 New Zealand white rabbits.
Pelvic organ prolapse (POP) has become one of the most common serious diseases affecting parous women. Weakening of pelvic ligaments plays an essential role in the pathophysiology of POP. Currently, synthetic materials are widely applied for pelvic reconstructive surgery.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!