Research Article Heating Characteristics of Films Prepared with Polymer-Graphite Composites Seojin Kim, 1 Weontae Oh , 1 Jong-Seong Bae, 2 Seong Baek Yang, 3 Jeong Hyun Yeum, 3 Jaehyeung Park, 1 Choonghyun Sung, 1 Jungsoo Kim, 4 and Jae-Cheon Shin 5 1 Division of Advanced Materials Engineering, Dong-eui University, Busan 47340, Republic of Korea 2 Busan Center, Korea Basic Science Institute, Busan 46742, Republic of Korea 3 Department of Bio-Fibers and Materials Science, Kyungpook National University, Daegu 41566, Republic of Korea 4 Pusan National University Yangsan Hospital, Yangsan 50612, Republic of Korea 5 Pohang Center for Evaluation of Biomaterials, Pohang 37668, Republic of Korea Correspondence should be addressed to Weontae Oh; wtoh2005@deu.ac.kr and Jae-Cheon Shin; jcshin@ptp.or.kr Received 8 May 2019; Revised 21 July 2019; Accepted 29 July 2019; Published 19 August 2019 Academic Editor: Andrea Camposeo Copyright © 2019 Seojin Kim et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Heating films were prepared by using poly(methyl methacrylate) and polybutadiene composites containing graphite. The heating film was prepared by casting the as-made polymer composite on the PET film. Copper electrodes were attached to both ends of the as-prepared film, and the heating characteristics of the film were analyzed while applying the DC voltage. The electrical conductivity and the heating temperature of the heating films depended on the size, the structure, the content, and the dispersion characteristics of the graphite in the composite. The electrical resistance of the heating film was controlled to adjust the heating temperature of the film. The relationship between the physical/chemical structure and the heating characteristics of the composite film was studied by measuring the heating temperature as functions of film thickness and resistance by using an infrared thermal imaging camera. The lower the film resistance, the higher the heating temperature of the film. The surface temperature was uniform throughout the film. 1. Introduction Heating film is a heating element that generates thermal energy from the film surface, based on the principle of Joule heating (also known as Ohmic heating) [1]. When copper electrodes are attached to both ends of a heating film and a rated voltage is applied on the film, thermal energy is gener- ated over the entire surface of the film. Generally, a heating film radiates thermal energy converted from electric energy. The temperature of a heating film can be easily controlled, and the use of the heating film does not pollute the air, so it has advantages in terms of hygiene and noise [2, 3]. For this reason, the heating films are widely used for home heating systems in Europe and the application areas have been expanded to the industrial fields of dryers, healthcare aids, and building materials as well as housing [4, 5]. In the heating film containing carbon materials as a con- ductive filler, the electrical resistances caused by the intercon- nection of a myriad of carbon particles generate the thermal energy when current is applied. The heating films prepared with carbon composites exhibit excellent electrical/thermal conductivity and the weatherability, and the research on the carbon-based heating technology has been actively con- ducted in the academic and industrial fields [6, 7]. A single- walled carbon nanotube (SWNT) has been used to prepare a transparent heating film, which showed heating character- istics with a transparency of over 90%. The heating films based on silver nanowires have been also reported [8–11]. However, this transparent heating film technology has limi- tations for industrial application due to expensive SWNT and Ag nanowires. In addition, such heating films have poor mechanical properties such as flexibility and brittleness. On Hindawi International Journal of Polymer Science Volume 2019, Article ID 3478325, 8 pages https://doi.org/10.1155/2019/3478325