Environmentally sustainable rice husk ash reinforced cardanol based polybenzoxazine bio-composites for insulation applications

K Krishnadevi,S Sriharshitha,M Alagar,S Devaraju,Y Keerthi Priya

doi:10.1007/s00289-019-02854-4

K Krishnadevi, S Sriharshitha + Show 3 more

Open Access

https://doi.org/10.1007/s00289-019-02854-4

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Abstract

Tri-substituted cardanol based benzoxazine with functionalized rice husk ash (CBz/FRHA) bio-composites were developed using renewable resource materials, and their thermal, electrical, and biological properties were studied by different analytical methods. The molecular structure of CBz was confirmed by nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy (FT-IR) techniques. Data resulted from thermal studies indicated that the incorporation of bio-based silica reinforcement effectively improved the thermal properties including Tg, thermal stability and char yield. Dielectric studies indicate that the bio-based composites possess the lower value of dielectric constant (low k—2.15) than that of neat matrix (low k—4.04). Further, the antimicrobial studies were carried out against Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Streptococcus bacteria using disk diffusion method and the results obtained confirm that the CBz/FRHA bio-composites possess an improved antibacterial behavior. Data resulted from different studies, and it is suggested that CBz/FRHA based bio-composites can be used as cost competitive materials in the form of adhesives, sealants, encapsulants and matrices for low-k insulation application in the field of microelectronics for high-performance applications.

Highlights

Vegetable oils such as soybean, tung, linseed, rapeseed, castor oil and cashew nut shell oil or cashew nut shell liquid (CNSL) have been used for a wide variety of applications [1, 2]
Further the surface modified rice husk ash (RHA) was confirmed by Thermogravimetric analysis (TGA) (Fig. 2)
The values of percentage char yield obtained from TGA for RHA and functionalized rice husk ash (FRHA) are 98% (5% weight loss due to the moisture in RHA) and 82%, respectively

Summary

Introduction

Vegetable oils such as soybean, tung, linseed, rapeseed, castor oil and cashew nut shell oil or cashew nut shell liquid (CNSL) have been used for a wide variety of applications [1, 2]. An attempt has been made to develop a bio-based composites using tri-substituted cardanol benzoxazine (CBz) and varying percentage weight ratio of functionalized silica obtained from rice husk ash.

Results

Conclusion