Abstract—In this research, waterglass based aerogel powder was prepared by sol–gel process and ambient pressure drying. Inspired by limited dust releasing, aerogel powder was introduced to the PET electrospinning solution in an attempt to create required bulk and surface structure for the nanofibers to improve their hydrophobic and insulation properties. The samples evaluation was carried out by measuring density, porosity, contact angle, heat transfer, FTIR, BET, and SEM. According to the results, porous silica aerogel powder was fabricated with mean pore diameter of 24 nm and contact angle of 145.9º. The results indicated the usefulness of the aerogel powder confined into nanofibers to control surface roughness for manipulating superhydrophobic nanowebs with water contact angle of 147º. It can be due to a multi-scale surface roughness which was created by nanowebs structure itself and nanofibers surface irregularity in presence of the aerogels while a layer of fluorocarbon created low surface energy. The wettability of a solid substrate is an important property that is controlled by both the chemical composition and geometry of the surface. Also, a decreasing trend in the heat transfer was observed from 22% for the nanofibers without any aerogel powder to 8% for the nanofibers with 4% aerogel powder. The development of thermal insulating materials has become increasingly more important than ever in view of the fossil energy depletion and global warming that call for more demanding energy- saving practices. Keywords—Superhydrophobicity, Insulation, Sol-gel, Surface energy, Roughness. I. INTRODUCTION HE wettability of solid surface is an important property of material that is controlled by the chemical composition and geometry of the surface [1], [2]. There are many applications for which a material must be water-resistant. The inadequacy of fossil fuels, which is the main resource for the industries and energy carriers, has highlighted the dependence of modern technology on cheap energy and resources. Thus, this is forcing humanity to rethink global energy strategies. In addition to a limited supply of carbon-based fuels worldwide, Z. Mazrouei-Sebdani is with the Department of Textile Engineering, Isfahan University of Technology, Isfahan, CO 84156-83111 Iran (phone: 031-3391-5033; fax: 031-3391-2444; e-mail: z.mazrouei@ tx.iut.ac.ir). A. Khoddami, was with the Department of Textile Engineering, Isfahan University of Technology, Isfahan, CO 84156-83111 Iran (phone: 031-3391- 5033; fax: 031-3391-2444; e-mail: khoddami@ cc.iut.ac.ir). H. Hadadzadeh is with the Department of Chemistry, Isfahan University of Technology, Isfahan, CO 84156-83111 Iran (phone: 031-3391-3240; fax: 031- 3391-3240; e-mail: hadad@ cc.iut.ac.ir). M. Zarrebini is with the Department of Textile Engineering, Isfahan University of Technology, Isfahan, CO 84156-83111 Iran (phone: 031-3391- 5022; fax: 031-3391-2444; e-mail: zarrebini@ cc.iut.ac.ir). the effect a rising CO 2 concentration in the earth’s atmosphere and its effect on the global climate, has become indubitably clear [3], [4]. Silica aerogels can have unusual properties, including high surface area, low density, low thermal conductivity, and good optical translucency [5]. This combination of properties makes hydrophobic silica aerogels attractive materials for use in applications [6]. One of the major characteristics of silica aerogels is their very low thermal conductivity, typically of the order of 0.015 Wm -1 K -1 at ambient temperature and relative Humidity [7]. In this research, waterglass based aerogel powder prepared via sol– gel and ambient pressure drying was introduced to the PET nanofibers in an effort to generate proper structure to improve the physical properties. II. EXPERIMENTAL A. Materials All chemicals were of analytical grade from Merck, Germany. TMCS was prepared from Daejung, Korea. B. Sample Synthesize The sodium silicate solution diluted by water (1/4 v/v) went through a long ion-exchange column filled with Amberlite IR 120 H resin. The initial pH of the silica sol was adjusted to 5 with diluted ammonia (1%) to be gelled and then, aged for 3 hours. Propan-2-ol (IPA), trimethylchlorosilane (TMCS), and n-Hexane were used for the solvent exchange and surface modification process for 1 day. The gel was air dried at room temperature for 1 day and 230ºC for 1 h, and then grounded gently with a ball mill (Pm10, Retsch, Germany). Fabrication of the Hybrid Aerogel/Nanofibers A mixture of PET chips in 1:1 (v/v) DCM and TFA was firstly stirred using a magnetic stirrer for 12 h and then by an ultrasonic stirrer (UP200 H lab device (200 W, 24 kHz)) for 20 min. a horizontal electro-spinning, STC-523 device, Japan was used for electrospinning process at a voltage of 13 kV. C. Characterization The bulk density was measured from known volume and mass of the aerogel piece. The porosity of the resulted aerogel was calculated using (1).  ൌ ቀ1 െ ఘ  ఘ ೞ ቁ ൈ 100 (1) A Novel Method to Manufacture Superhydrophobic and Insulating Polyester Nanofibers via a Meso-Porous Aerogel Powder Z. Mazrouei-Sebdani, A. Khoddami, H. Hadadzadeh, M. Zarrebini T World Academy of Science, Engineering and Technology International Journal of Materials and Metallurgical Engineering Vol:9, No:1, 2015 71 International Scholarly and Scientific Research & Innovation 9(1) 2015 ISNI:0000000091950263 Open Science Index, Materials and Metallurgical Engineering Vol:9, No:1, 2015 publications.waset.org/10000241/pdf