Development Of A Functional Textile Material For Grain Storage To Restrain Carcinogenic Mycotoxin Contamination

The grain contaminated with mycotoxin pose a great threat for human and animal's health.Based on principle of fungi growth and mycotoxin production,many methods,including good agricultural practices,fumigation,chemical control and new packaging material development,are used to minimize contamination.However,these methods have not been widely adopted because of the high cost without obvious effect or/and secondary pollution.The research contents and methods were introduced in this paper.With the purpose of development of a functional packaging material for grain storage to reduce the mycotoxin contamination,the present study firstly analyzed and calculated the change of condition in the micro-ecosystem,including the moisture content,temperature and gas composition when 25kg maize were ideally stored with the influence of respiration of stored kernels or external environment respectively.From the perspective of mycotoxin reduction,the packaging material was designed,including fiber selection,mass per unit area of nonwovens determination and composite structure design.The results reveal that if the weight of the jute fibers containing in the packaging materials is higher than 25kg,they could efficiently absorb the water vapor or water liquid generated during the maize storage;when the oxygen transmission rates of packaging material is 2 cm3/(cm2.24hr),the weight of jute fibers should no less than 50.36g.If the dimension of the pure jute fabric is 580mmx900mm,the mass per unit area should be more than 65.51 g/m2 so that the packaging material for grain storage may obtain the function to prevent the maize from aflatoxin infection.According to the conclusioin above and technical requirements,took jute fibers as the main raw materials and blended them with hot-melting evenly.Then,manufacture the jute thermal-bonding nonwovens.The results indicate that the tensile strength increase if the webs are bonded by needle-punch and thermal-bonding;Meanwhile,the tensile strength increased with the hot-melting fiber increased.Based to the above conclusion,the absorption/desorption properties of jute thermal-bonding nonwovens are further studied in this paper.In order to simulating the absorption/desorption properties of the jute thermal-bonding nonwovens under the practical environment,the absorption/desorption moisture regain,the initial rates of the absorption and desorption were tested and analyzed.The results shows that the absorption and desorption moisture regain increased with amount of hydrophobic fiber increased under the condition with high temperature;the change of the moisture regain happened in the first twenty minutes.As the content of the hydrophobic fiber rose,both of the maximal moisture regain and the initial rate of the absorption and desorption are increased.In additional,the moisture regain were vulnerable to the changing environment.The moisture regain of the jute thermal-bonding nonwovens increased when temperature decrease sharply to the dew temperature under the condition with high relative humidity;the cyclic moisture reduce with the increase of number of cycle.Determined the melting pointing and oxygen transmission rate of each type of film and observed the cross-section,it found that the films,including Film A,Film B,Film C and Film D,comprise of three layers.The thickness of each layer is different from others.The results also indicated that Film A are fabricated by two kinds of polymers with melting points of 140? and 177?,respectively;Film B are fabricated by two kinds of polymers with melting points of 117? and 175.3?,respectively;Film C are fabricated by three kinds of polymers with melting points of 121?,171? and 181?,respectively.Each film shows a good property of oxygen resistant.The laminate process and the oxygen transmission rate of the composite are studied in the paper in the end.Two types of jute thermal-bonding nonwovens were prepared.The percent of jute fiber in each type of nonwovens was 50%and 80%,respectively.Then,the composites were manufactured through laminating the film on the jute thermal-bonding nonwovens at different temperatures and pressure.The factors that influencing the thermal-bonding property were analyzed based on the observation of bonding interface and bonding strength of the composites.The results show that it is benefit for bonding process with less jute fibers on the surface of jute thermal-bonding nonwovens;Film D has best bonding property compared to any other films.The optimal temperature is round(125-130)? and the optimal pressure is in the range of(4-8)MPA when the Film D was laminated on the thermal-bonding nonwovens with 50%percent of jute fibers.The oxygen transition rate of composite is 0.7011 cm3/m2.24hr,which satisfied the requirements of packaging material for mycotoxin inhibition.