? ? ? ? Because of the particularity of agricultural production, the irrigation membrane needs to meet the following requirements:?①Good weather resistance. if used in high latitude areas in the field, membrane needs to withstand some strict tests such as, in the presence of water, it is subjected to freezing and thawing without damage, i.e., the pore size and permeability of the membrane must not change.?②Low or no adsorption. Source of agricultural irrigation water is pretreatment and local water, so the water contains organic matter, biomass, hardness and other ions and other complex components. In order to improve the efficiency and service life, the adsorption of membrane must be very low, anti-pollution ability must be very strong.?③Resistance to a wide range of pH values and corrosion of added substances in irrigation, due to regional differences and added matters such as fertilizers, pesticides and other substances, the film's PH adaptability, polarity and solvent properties need to be good.?④Resistance to microbial attack and being not conducive to the breeding of microorganisms. Due to large number of microorganisms in agricultural water, membrane life will be very short if microbes erode membrane; also the?water permeability of membrane will decrease quickly if Microbial is breeding.?⑤Good pore size distribution and high water permeability. Good pore size distribution is conducive to uniform water distribution, and high water permeability is conducive to reducing the use of membrane area to save costs.?⑥Excellent permanent hydrophilic.? Being Fully hydrophilic and hydrophilic should not be affected by geographical, environmental, filter media, the time of use.?⑦Good machinability.? Due to the low cost requirements of agriculture, the after processing use melting processing as the main material, structure is mainly polyethylene which is durable and cheap. Therefore, it is required that the hot melt welding of PE and PE should good.?⑧high performance Cost rate. Membrane procurement costs should be low, long life needs. From the above considerations, XH series membrane has high application value.