To improve the stability and ductility of polylactic acid (PLA), chain extender or crosslinking agent of phosphite functional polysilsesquioxane (PPSQ) was synthesized by the reaction of phosphite group with the amino group of poly(amino-epoxy)silsesquioxane (PSQ). First, the reaction of PPSQ with PLA was characterized by molecular weight ( ) and melt mass flow rate (MFR) of PLA after melting reaction. The results showed a 6.6% increase in the of PLA and a 24.5% decrease in MFR value at the PPSQ loading content of 2 wt% in PLA, indicating that PPSQ takes chain extension or crosslinking in PLA. Then, this result was further supported by the thermal stability improvement of PLA, which was testified by the increase of oxidative activation energy and the oxygen onset temperature (OOT) value. PPSQ improved the water resistance and mechanical properties of PLA. The hydrolysis rate decreased by 46.8%, and the tensile strength and impact strength increased by 17.2% and 89.4%. Taken together, these results indicate that the addition of PPSQ can produce the PLA with excellent thermal stability, hydrolytic stability and mechanical properties.
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http://dx.doi.org/10.1039/c9ra03147b | DOI Listing |
Lasers Med Sci
January 2025
Department of Stomatology, the First Medical Centre, Chinese PLA General Hospital, Beijing, 100853, China.
Objective: This study evaluated dentin morphology and pulp cavity temperature changes during nanosecond‑ and microsecond‑pulse Er, Cr: YSGG laser debonding restoration and residual adhesive.
Materials And Methods: Ten caries-free teeth had their enamel removed perpendicular to the long axis, followed by bonding of glass ceramic restorations. The samples were randomly divided into two groups and subjected to Er, Cr: YSGG laser (3 mJ, 100 Hz, 100 ns), (3 mJ, 100 Hz, 150 µs) for debonding of restoration and residual adhesive on dentin surfaces.
Small
January 2025
Guangzhou Institute of Blue Energy, Knowledge City, Huangpu District, Guangzhou, 510555, P. R. China.
Physiological wound healing process can restore the functional and structural integrity of skin, but is often delayed due to external disturbance. The development of methods for promoting the repair process of skin wounds represents a highly desired and challenging goal. Here, a flexible, self-powered, and multifunctional triboelectric nanogenerator (TENG) wound patch (e-patch) is presented for accelerating wound healing through the synergy of electrostimulation and photothermal effect.
View Article and Find Full Text PDFMater Today Bio
February 2025
Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, 100048, PR China.
A meniscus injury is a common cartilage disease of the knee joint. Despite the availability of various methods for the treatment of meniscal injuries, the poor regenerative capacity of the meniscus often necessitates resection, leading to the accelerated progression of osteoarthritis. Advances in tissue engineering have introduced meniscal tissue engineering as a potential treatment option.
View Article and Find Full Text PDFACS Nano
January 2025
Bio-Organic Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
The morphology of nanodrugs is of utmost importance in photothermal therapy because it directly influences their physicochemical behavior and biological responses. However, clarifying the inherent relationship between morphology and the resultant properties remains challenging, mainly due to the limitations in the flexible morphological regulation of nanodrugs. Herein, we created a range of morphologically controlled nanoassemblies based on poly(ethylene glycol)--poly(d,l-lactide) (PEG-PLA) block copolymer building blocks, in which the model photosensitizer phthalocyanine was incorporated.
View Article and Find Full Text PDFJ Biomed Mater Res A
January 2025
PRISM Research Institute, Technological University of the Shannon: Midlands Midwest, Athlone, Ireland.
This study provides a comprehensive investigation of antimicrobial additives (ZnO/AgNPs and SiO/AgNPs) on the properties of biodegradable ternary blends composed of poly(hydroxybutyrate) (PHB), poly(lactic acid) (PLA), and polycaprolactone (PCL) by examining the morphology, thermal stability, crystallinity index, and cell viability of these blends. Overall, transmission electron microscopy (TEM) analysis revealed that AgNPs and SiO exhibited comparable sizes, whereas ZnO was significantly larger, which influences their release profiles and interactions with the blends. The addition of antimicrobials influences the rheology of the blends, acting as compatibilizers by reducing the intermolecular forces between biopolymers.
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