Dispersion of Functionalized Silica Micro- and Nanoparticles into Poly(nonamethylene Azelate) by Ultrasonic Micro-Molding
نویسندگان
چکیده
Ultrasound micro-molding technology has proved useful in processing biodegradable polymers with minimum material loss. This makes this technology particularly suitable for the production of biomedical microdevices. The use of silica (SiO2) nanoparticles is also interesting because of advantages like low cost and enhancement of final properties. Evaluation of the capacity to create a homogeneous dispersion of particles is crucial. Specifically, this feature was explored taking into account microand nano-sized silica particles and a biodegradable polyester derived from 1,9-nonanodiol and azelaic acid as a matrix. Results demonstrated that composites could be obtained with up to 6 wt. % of silica and that no degradation occurred even if particles were functionalized with a compatibilizer like (3-aminopropyl) triethoxysilane. Incorporation of nanoparticles should have a great influence on properties. Specifically, the effect on crystallization was evaluated by calorimetric and optical microscopy analyses. The overall crystallization rate was enhanced upon addition of functionalized silica nanospheres, even at the low percentage of 3 wt. %. This increase was mainly due to the ability of nanoparticles to act as heterogeneous nuclei during crystallization. However, the enhancement of the secondary nucleation process also played a significant role, as demonstrated by Lauritzen and Hoffmann analysis.
منابع مشابه
Application of Nanoanalysis: Amine-Functionalized Mesoporous Silica nanoparticles for Mercury Speciation in Human Samples
Mercury (Hg) causes hazardous cumulative effects in humans; like central nervous system disorders,hypertension and chromosomal aberrations. Therefore, due to high toxicity and bioaccumulationfactor, mercury determination and speciation in human blood is very important. A sensitive,accurate, precise and inexpensive method was demonstrated for preconcentration and speciationof ultra-trace mercury...
متن کاملAcoustic Emission Monitoring for Ultrasonic Cavitation Based Dispersion Process
In the manufacturing of micro/nanocomposite materials, micro/nanoparticles need to be dispersed evenly into the base materials. However, due to their high surface-to-volume ratio and high surface energy, the micro/nanoparticles tend to agglomerate and cluster together. Ultrasonic cavitation is effective to disperse micro/nanoparticles. However, works on correlating the cavitation parameters wit...
متن کاملHigh Performance Nanocomposite Cation Exchange Membrane: Effects of Functionalized Silica-Coated Magnetic Nanoparticles
Nanocomposite cation exchange membranes (CEMs) were prepared by adding various amounts of functionalized silica-coated magnetite nanoparticles to the sulfonated polyethersulfone (sPES) polymeric matrix. The particles were synthesized first by the co-precipitation method (M0). Different surface modifications were then carried out on them by grafting three functional groups of mercaptopropyl, pro...
متن کاملPreferential Incorporation of Azelaic Acid Units into the Crystalline Phase of the Copoly(Alkylene Dicarboxylate) Derived from 1,9-Nonanediol and an Equimolar Mixture of Pimelic and Azelaic Acids
The crystalline structure of two biodegradable odd-odd polyesters (i.e., poly(nonamethylene pimelate) (PES 9,7) and poly(nonamethylene azelate) (PES 9,9)) was investigated by means of electron and X-ray diffraction of single crystals and oriented fibers, respectively. Truncated rhombic crystals were obtained with an aspect ratio that was strongly depended on the supercooling degree. The crystal...
متن کامل