Study On Release Of The Harmful Substances In Wood And Wood-plastic Composites Under The Household Environment With Environmental Chamber Method

As a new type of composite materials, wood-plastic composites (WPC) have the advantages in the resource utilization and environmental protection. Therefore, it has been attracted much attention since its birth. Meanwhile, wood-plastic composites have a very wide application range.All fields which use wood or wood materials as main materials can use composites as substitution, such as wooden buildings and all kinds of decoration materials, furniture, packaging material, sports stationery, etc. Wood materials, as a traditional household decoration materials, have been developed for thousands of years. But after entered 21st century, a series of problems, such as the severe shortage of global forest resources, destruction of the ecological environment and global warming, are plaguing the human society. In order to improve the current environmental situation, all countries in the world have proposed a variety of measures to limit the forest harvesting. As a result, the timber resources which can be used in the forest industry is becoming less and less. Obviously, the wood-plastic composites is a good choice to replace the wood materials.People spend 1/3 of their life time at home. As an important place in people’s daily life, the ambient air quality of household environment is directly related to the occupants’physical and mental health. The air is the carrier of harmful substances in household environment, so people’s health is threatened by breathing contaminated air. The bad household environment not only affects the comfort of people living, also influences the health of occupants. Therefore, in addition to meeting people’s requirement for its functions, all household material should also have the characteristics of low emission of harmful substances. This subject aims to study the release of harmful substances of wood-plastic composite materials and wood materials in household environment. As there are varieties of harmful substances released from materials, this subject will only choose several kinds of harmful substances which are common concern of consumers. Based on our national standard, the subject will focus on the release of the formaldehyde, benzene compounds benzene, toluene, xylene and total volatile organic compounds (TVOC) in household environment.There are all kinds of detection method of harmful substances in household materials. People should select the appropriate test methods according to the characteristics of different materials and different types of hazardous substances. The research methods of this subject will take into account of various factors as comprehensive as possible. Environmental chamber method, which is one of international universal methods to study and detect the release of harmful substances with wide range of application, including building materials, mattresses, electronic products (printers, computers, etc.) release of harmful substances, as well as passenger cars within detection of harmful substances, has become a hot research field. Environmental chamber method is not only applied to test different types of harmful substances released by a single material, but also applied to test different types of harmful substances released by a integrally formed article which is a combination of various materials. Because of its high simulation of the real environment, this method has become one of the authoritative research and testing methods of harmful substances release. Therefore this study select environmental chamber method as the study method to compare the release of harmful substances of wood and wood-plastic composite materials in household environment.This subject does reach on the arrangement of household environment decoration materials (mainly refers to the furniture and floor) in Jinan, Qingdao, Weifang, Yantai and Dezhou etc, making sure the volumetric loading rate (the rate between the outlook volume of furniture and floor and volume of environmental chamber). Using 100 m3 Environmental chamber respectively collects the data of release of harmful substances in different household environment (bedroom, sitting room, study) and different material samples (wood, wood and plastic materials).Using adsorption tube with Tenax TA adsorbent to collect the certain volume mixed gas which contains volatile organic compounds released from the sample, volatile organic compounds in the mixed gases will remain on the adsorption tube. Analyzing the collected volatile organic compound by secondary thermal stripping device, it will enter into gas chromatography equipped with capillary column by the inert gas carrier through the cold trap. With mass spectrometry detector, the peak time makes qualitative and peak area makes quantitative. Using air sampler and large bubble absorption tube to make a reaction between formaldehyde of harmful substance from the environmental chamber and phenol to generate piperazine, which can be oxidized to be glaucous compound formation by high ferric iron in acid solution. According to the color shades, people can determine the quantity by colorimetry. According to the testing result, people can compare the release of harmful substances between wood and wood-plastic composite material and study the advantage of wood-plastic composite material. According to the testing result, people can find that wood plastic composite is better than wood materials on release of formaldehyde, tamoxifen (benzene, toluene, xylene) and TVOC.Through the experiments of this project, people will discover that WPC releases less harmful substances than traditional wood materials in household environment. Furthermore, it has the advantages of resources using and environmental protection, so people hope wood-plastic composites can be the first to be fully applied to the home decoration field, replacing the current wooden materials.This paper describes the release of harmful substances of WPC in household environment and takes the release of harmful substances of traditional wood in household environment as a reference, comparing the release condition of harmful substances of the two materials in household environment. It affirms the possibility of WPC to replace traditional wood materials in the field of home decoration, and foretells its application prospect.