Preparation And Properties Of Water- Repellent PET Polyester Fiber Based Based On Blending Method

PET fabric has the advantages of excellent wrinkle and shape retention,dimensional stability,good elasticity,high strength and good chemical stability and heat resistance.PET fiber has the largest output in the chemical fiber industry and is widely used in many fields.However,there are also problems such as excess capacity,relatively low differentiation rate,and low added value.With the rapid development of society,people have put forward higher requirements for the fabric in addition to the basic conventional performance in terms of functionality.Among them,the waterrepellent fabric has excellent surface properties such as waterproof,anti-fouling and easy to clean,which makes it have great application potential and development prospects.Compared with other commonly used chemical and natural fibers,PET fiber has poor hydrophilicity due to its own structural characteristics.On this basis,it is necessary to improve its water repellency,and then expand the application areas of PET fiber..In this paper,the blending modification method is adopted,polydimethylsiloxane(PDMS)masterbatch and pentaerythritol stearate(PETS)as modifiers were used to modify the water repellency of PET.On the basis of the evaluation and analysis of the basic properties of the blended modified PET chips,the modified chips were melt-spun,and the basic properties and water repellency of the modified fibers were tested.Finally,the fiber made of the appropriate draft ratio was selected.Into a fabric,test and analyze the moisture permeability of the fabric.The specific research contents are as follows:(1)Firstly,PDMS,PETS and PET were used for melt blending and granulation through a twin-screw extruder.At the same time,the properties of blended modified PET chips in two different systems were studied.Through the Fourier infrared test and nuclear magnetic resonance spectroscopy analysis of the PDMS masterbatch and PETS,the relationship between the structure of the modifier and the water repellent mechanism was clarified.The surface contact angle test of the blended slices was used to evaluate the water-repellent performance.The structure shows that the PDMS blend system increases the contact angle of PET from 72.6 ° to 96.2 °,and the PETS blend system increases the contact angle of PET from 68.6 ° to 110.3 °.Both of modifiers all improve the water repellency of PET chips to a certain extent.The compatibility of the two modifiers with PET was evaluated by scanning electron microscope(SEM)test.When the addition amount of PDMS masterbatch is 1%-4%,PDMS has little effect on the structure of PET,and it can be evenly distributed in PET.PETS is mainly distributed and sliced surface layer due to its low melting point.The non-isothermal crystallization kinetics analysis of 2% and 4% PDMS blended slices and pure PET finds that the semi-crystallization time of the system decreases with the addition of PDMS,indicating that the crystallization rate of the system is accelerated to a certain extent.The rotational rheological test results of blended slices shows that with the addition of modifier,the non-Newton index of the system decreases and the apparent viscosity increases,which provides guidance for the subsequent spinning process adjustment.(2)The analysis of the mechanical properties of the modified fibers reveals that the PDMS blended modified fibers gradually decreases the breaking strength of the fibers as the PDMS content increases,while the breaking elongation of the fibers gradually increases.The mechanical properties of PETS blend modified fiber are not significantly different from conventional PET fiber.The addition of PDMS masterbatch increases the steric hindrance of the PET molecular chain to a certain extent,which affects its ordered arrangement,and the orientation crystallinity of the fiber is reduced.Due to the low initial addition of PETS and the mass loss caused by high temperature during the spinning process,the mechanical properties and orientation of PETS modified fibers do not change significantly.The addition of the two modifiers has improved the water-repellent performance of the fiber to a certain extent.However,compared with the water-repellent performance of the modified chips,the improvement of the fiber has been reduced to a certain extent.Because the addition of PDMS reduces the orientation crystallinity of the fiber,which improves the dyeing performance of the fiber to a certain extent,the dyeing performance of the modified fiber of the PETS system has not changed significantly.The test result of the moisture permeability of the fabric shows a downward trend,indicating that the addition of the modifier improves the water repellency of the fabric to a certain extent,but there is still a certain gap from the actual application.