Preparation and characterization of polycarbonate nanocomposites based on surface-modified halloysite nanotubes

• Published in: Polymer journal Vol. 46; no. 5; pp. 307 - 312
• Main Authors: Jing, Hui, Higaki, Yuji, Ma, Wei, Xi, Jiang, Jinnai, Hiroshi, Otsuka, Hideyuki, Takahara, Atsushi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.05.2014; Nature Publishing Group
• Subjects: 639/301/357; 639/638/455/941; 639/638/455/957; 639/638/455/958; Applied sciences; Biomaterials; Bioorganic Chemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Composites; Dispersions; Exact sciences and technology; Forms of application and semi-finished materials; Infrared spectroscopy; Nanocomposites; Nanotubes; original-article; Polycarbonates; Polymer industry, paints, wood; Polymer Sciences; Scanning electron microscopy; Surface chemistry; Surfaces and Interfaces; Technology of polymers; Thermal stability; Thin Films; thermal stability; polycarbonate; glass transition temperature; halloysite nanotubes; clay nanocomposites; Clay; Mixing; Chemical precipitation; Dispersion degree; Silicon Organic compounds; Nanotube; Experimental study; Molecular relaxation; Thermal stability; Coupling agent; Compression molding; Morphology; Nanocomposite; Manufacturing; Primary amine; Polycarbonate; Activation energy; Growth from solution; Modified material
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1038/pj.2013.100

Halloysite nanotubes (HNTs) modified by a chemical vapor adsorption (CVA) process remarkably improve the thermal stability of polycarbonate nanocomposites. HNTs were modified with N -(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS) and n -octadecyltrimethoxysilane (OTMS) using a CVA process. Both Fourier-transform infrared spectroscopy and thermogravimetric analysis showed that the modifiers were immobilized on the HNT surfaces. Polycarbonate (PC)/HNT nanocomposites were prepared with the modified HNTs by a combination of solution mixing, precipitating and compression molding. The dispersion states of modified HNTs in PC nanocomposites were observed by optical microscopy, scanning electron microscopy and transmission electron microscopy. The storage modulus ( E ′) and thermal stability of the PC nanocomposites were enhanced by the modified HNTs. OTMS-modified HNT/PC nanocomposites showed higher performance than AEAPS-modified HNT/PC nanocomposites due to the stronger affinity of the hydrophobic alkyl groups of OTMS for the polymer matrix. This study demonstrates a low amount of halloysite nanotubes modified by a CVA process remarkably improve the thermal stability of PC nanocomposites. The n -octadecyltrimethoxysilane modifier bearing a longer alkyl tails shows stronger affinity with the matrix than the N -(2-aminoethyl)-3-aminopropyltrimethoxysilane modifier bearing shorter alkyl tails with amino group.