Rheological and Crystallization Properties of ABS/PA6-Compatibilized Blends via In Situ Reactive Extrusion

Abstract High performances fiber and improved interfacial interaction can enhance the properties of polymer composites. Herein, microcrystalline cellulose (MCC) was oxidized by H2O2/CuSO4, a new Fenton process, to achieve oxidized MCC (OCNCs) with 16 ± 1% carboxyl content. Noteworthy, the thermal stability of OCNC was superior to CNC prepared by acid hydrolysis. Interestingly, the primary alcohol groups of MCC were selective oxidized and OCNCs achieved 11.0 nm, 231.6 nm and 72% of average diameter, length and degree of crystallinity, respectively. Then glycerol, starch and OCNCs were reactive extruded to fabricate TPS/OCNC bionanocomposites and their structure and performances were evaluated systematically. Strikingly, significant improvement in glass transition temperature (from 63.1 to 94.5 °C) and notch impact strength (from 1.3 to 3.9 kJ/m2) were noted for the amorphous TPS/OCNC with 1 wt% OCNC, and its tensile strength achieved 20.5 MPa, simultaneously. The improved mechanism of these performances was assigned to In-Situ forming “Carboxyl-Hydroxyl” hydrogen bonds which acted as the physically cross-linking interactions and improved the interfacial compatibility. We showcase Fenton reaction and reactive extrusion as the facile strategy to prepare sustainable and biodegradable TPS/OCNC bionanocomposites with properties more suitable for daily applications to replace petroleum-based plastic and eliminated the pollution of “microplastics.”

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Effects of Methylenediphenyl 4,4’-Diisocyanate and Maleic Anhydride as Coupling Agents on the Properties of Polylactic Acid/Polybutylene Succinate/Wood Flour Biocomposites by Reactive Extrusion

Materials ◽

10.3390/ma13071660 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1660

Author(s):

Young-Rok Seo ◽

Sang-U Bae ◽

Jaegyoung Gwon ◽

Qinglin Wu ◽

Birm-June Kim

Keyword(s):

Maleic Anhydride ◽

Polylactic Acid ◽

Viscoelastic Properties ◽

Interfacial Adhesion ◽

Wood Flour ◽

Flexural Modulus ◽

Reactive Extrusion ◽

Coupling Agents ◽

Polybutylene Succinate

Polylactic acid (PLA)/polybutylene succinate (PBS)/wood flour (WF) biocomposites were fabricated by in situ reactive extrusion with coupling agents. Methylenediphenyl 4,4’-diisocyanate (MDI) and maleic anhydride (MA) were used as coupling agents. To evaluate the effects of MDI and MA, various properties (i.e., interfacial adhesion, mechanical, thermal, and viscoelastic properties) were investigated. PLA/PBS/WF biocomposites without coupling agents revealed poor interfacial adhesion leading to deteriorated properties. However, the incorporation of MDI and/or MA into biocomposites showed high performances by increasing interfacial adhesion. For instance, the incorporation of MDI resulted in improved tensile, flexural, and impact strengths and an increase in tensile and flexural modulus was observed by the incorporation of MA. Specially, remarkably improved thermal stability was found in the PLA/PBS/WF biocomposites with 1 phr MDI and 1 phr MA. Also, the addition of MDI or MA into biocomposites increased the glass transition temperature and crystallinity, respectively. For viscoelastic property, the PLA/PBS/WF biocomposites with 1 phr MDI and 1 phr MA achieved significant enhancement in storage modulus compared to biocomposites without coupling agents. Therefore, the most balanced performances were evident in the PLA/PBS/WF biocomposites with the hybrid incorporation of small quantities of MDI and MA.

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