American Journal of Engineering Research (AJER) 2016 American Journal of Engineering Research (AJER) e-ISSN: 2320-0847 p-ISSN : 2320-0936 Volume-5, Issue-8, pp-43-49 www.ajer.org Research Paper Open Access www.ajer.org Page 43 A Comparative Study of the Thermal Insulation Properties of Jute and Jute - Polyester fibre Blended Nonwoven Fabrics Prof. Swapan Kumar Ghosh 1 , Satyaranjan Bairagi 2 , Souranil Dutta 3 , Rajib Bhattacharyya 4 1 ( Professor, Department of Jute and Fibre Technology, University of Calcutta,35, Ballygunge Circular Road, Kolkata- 700019, West Bengal, India) 2 (Senior Research Fellow, Department of Jute and Fibre Technology, University of Calcutta,35, Ballygunge Circular Road, Kolkata- 700019, West Bengal, India) 3 (M.Tech Final Semester Student, Department of Jute and Fibre Technology, University of Calcutta,35, Ballygunge Circular Road, Kolkata- 700019, West Bengal, India) 4 (Teaching associate, Department of Jute and Fibre Technology, University of Calcutta,35, Ballygunge Circular Road, Kolkata- 700019, West Bengal, India) ABSTRACT: Materials based on natural fibres are now becoming increasingly popular as thermal insulating material. Due to its low mass, density and cell structure, they show fairly good thermal insulation properties, often better and more advantageous than synthetic fibres. A great benefit of the insulation property based on natural fibres is not only a low value of thermal conductivity but also the natural character of these fibres. This paper delineatesto develop different blends of fibres comprising of jute and other fibres like recycled polyester (PET) and low melt bi-component fibres (PET) to produce needle punched nonwoven fabrics for using as thermal insulating material and to assess and compare the different functional properties of the developed nonwoven fabric samples for their suitability as thermal insulating material. Keywords: Thermal Insulation, CLO value, Air permeability, gsm, Thickness I. INTRODUCTION Thermal properties like thermal conductivity, thermal resistance, thermal insulation, etc. are important in many textile applications such as apparel, blankets, and sleeping bags, interlinings, building insulation, automobiles, aircraft and industrial process equipment [1]. In fact, these thermal properties are fundamental to determine the heat transfer through fabrics [2]. The thermal property of fabric is very important for both its thermal comfort and protection against challenging weather conditions [3]. The different types of textile materials which are generally used as thermal insulation media are mostly in nonwoven, woven and knitted forms. Thermal conductivity of needled nonwoven structures can be predicted with high accuracy using model with fabric thickness, porosity and structure along with applied temperature as was investigated by Mohammadi et al. [4]. Jirsak et al. concluded that thermal conductivity decreases with increasing material density [5]. Morris concluded that when two fabrics have equal thicknesses but different densities, fabric with lower density shows greater thermal insulation [6]. Abdel-Rehim et al. studied heat transfer through different fabrics made by polypropylene and polyester mass in a range from 400 to 800 g/m2 and they concluded that the investigated fabrics have high thermal performance and thermal response as insulators [7]. Saleh investigated properties of needled lining produced from polyester, cotton and recycled fibre and concluded that fabric thickness, mass and fibre type affect the thermal properties of the fabric [8]. In the same study the compressed linings show lower thermal insulation properties compared with non-compressed which was explained by a possible amount of trapped air of non-compressed nonwoven lining which provides greater thermal insulation. The calendering process gives a more compact structure of nonwoven fabrics, thus resulting in a controlled and predictable compressibility. With calendering needled polypropylene nonwoven fabrics the range of porosity becomes narrow when the characteristic opening sizes is reduced [9]. The influence of the calendering process of polypropylene nonwoven geotextiles on water permeability under different loads, as well as pore characteristics have been recently investigated and it has been concluded that additional bonding with calendering needled polypropylene nonwoven geotextiles provides a more controlled and predictable performance considering only needled geotextiles [10]. Debnath and Madhusoothanan have studied thermal resistance and air permeability of