Abstract
In this study, the montmorillonite (MMT) clay was modified with NH4Cl, and then the structures were exfoliated or intercalated in a polylactic acid (PLA) matrix by a torque rheometer in the ratio of 0.5, 3.0, 5.0 and 8.0 wt%. X-ray diffraction (XRD) revealed that the organic modified-MMT(OMMT) was distributed successfully in the PLA matrix. After thermal pressing, the thermal stability of the mixed composites was measured by a TGA. The mixed composites were also blended with OMMT by a co-rotating twin screw extruder palletizing system, and then injected for the ASTM-D638 standard specimen by an injection machine for measuring the material strength by MTS. The experimental results showed that the mixture of organophilic clay and PLA would enhance the thermal stability. In the PLA mixed with 3 wt% OMMT nanocomposite, the TGA maximum decomposition temperature (Tmax) rose from 336.84 °C to 339.08 °C. In the PLA mixed with 5 wt% OMMT nanocomposite, the loss of temperature rose from 325.14 °C to 326.48 °C. In addition, the elongation rate increased from 4.46% to 10.19% with the maximum loading of 58 MPa. After the vibrating hydrolysis process, the PLA/OMMT nanocomposite was degraded through the measurement of differential scanning calorimetry (DSC) and its Tg, Tc, and Tm1 declined.
Highlights
Biodegradable polymers have been intensively studied due to the depletion of fossil energy and its impacts on the environment [1,2,3]
With various amounts of OMMT, the primary diffraction peak appeared at 2θ = 2.52 (d = 34.9 nm), indicating that the interlayer distance of OMMT was extended by 15.6 nm and the exfoliation in the Polylactic acid (PLA) substrate had occurred
PLA contains the hydrolyzable ester function group, which could be hydrolyzed into lactic acid, and metabolized into CO2 and H2 O via Kreb’s cycle
Summary
Biodegradable polymers have been intensively studied due to the depletion of fossil energy and its impacts on the environment [1,2,3]. Biodegradable polymers, defined by the American Society for Testing and Material (ASTM) as being degradable by reacting with microbes, such as germs and fungi, can re-nourish soils during composting. In other words, these polymers possess sustainability and eco-efficiency. Polylactic acid (PLA), one of the polymers, represents the best environmentally friendly product. It has a hydrolyzable ester functional group, enabling its waste to be naturally decomposed to H2 O and CO2 during composting [4]. PLA is so far the most economical and competitive biodegradable polymer [5,6,7,8,9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
