In this study, Turkish bentonite (BN)
mineral is subjected to silane treatment in order to enhance its compatibility for poly(lactic acid) (PLA). Neat and
surface silanized BN powders are compounded with PLA using melt blending
process at the concentrations of 5, 10, 15 and 20 wt%. Surface characteristics
of BN samples are examined by infrared spectroscopy. Mechanical,
thermo-mechanical, water resistance, melt flow and morphological investigations
of composites are performed by tensile and impact tests, dynamic mechanical
analysis (DMA), water absorption test, melt flow rate test (MFR) and scanning
electron microscopy (SEM) analysis, respectively. Mechanical test results show
that BN additions lead to increase in tensile strength and modulus of PLA. The
maximum improvement is obtained for 15 wt% of silanized BN containing
composite. Silanized BN filled PLA displays higher impact performance compared
to untreated BN sample. Impact energy values of composites increase with
increase in loading ratio. Silanized BN containing composite with 20 wt% concentration
gives the highest storage modulus according to the DMA study. Glass transition
temperature of PLA is improved by the inclusions of all BN samples. Additions
of BN make slight decreases on MFR value of PLA. However, these reductions are
found to be negligible in terms of its effect on processing of material. Water
uptakes of composites are found to be higher than that of PLA. Composites
containing silanized BN have lower water absorption values than neat BN samples
due to the hydrophobicity of silicon containing surface. SEM characterization
reveals that more homogeneous dispersion in PLA matrix is observed for silane
treated BN compared to neat BN particles thanks to improvement of interfacial
adhesion between BN and PLA matrix.
Primary Language | English |
---|---|
Subjects | Engineering |
Journal Section | Articles |
Authors | |
Publication Date | March 31, 2020 |
Published in Issue | Year 2020 |