| In recent years,the interface of solid with bionic superhydrophobic property has a wide range of applications in many fields due to their properties of self-cleaning,oil-water separation,corrosion resistant,anti-freezing,prevent mist,etc.There are two factors are determining the wetting properties of solid surfaces in the fabrication process.The prerequisite is a roughness solid material surface with micron and nanometer scale structure.And the low surface energy material is the second requirement.In this thesis,we built the superhydrophobic surfaces based on the cellulose material which is an abundant natural polymer in the nature.As the basement,the hydrophilic cellulose materials were endowed the hydrophobic properties with the fluorine-free and non-toxic modifier.The hydrophobic cellulose could expand the application range of cellulose materials.At the same time,some reagents with friendly environment were added in the cellulose materials system to provide the additional properties about the flame retardancy or electrical conductivity etc.in the process of preparation.This thesis mainly covers the following aspects:1.A simple chemical reaction of FeCl3 and NaOH was used to deposit the Fe(OH)3particles on the filter paper surface.The Fe2O3 nanoparticles was obtained after pyrolyzing the Fe(OH)3 and increased the roughness of filter paper surface.The superhydrophobic Fe2O3/STA FP filter paper with high adhesion was prepared by dipping the Fe(OH)3 FP into the stearic acid(STA)solution which was low surface energy reagent.The surface structure and composition of the Fe2O3/STA FP were detected by SEM,IR,XPS and XRD.It proved that the filter paper surface has been covered with Fe2O3 particles and the STA was also successfully modified on the surface.The Water Contact Angle(WCA)test showed that the WCA values of modified filter paper reach to 151°±2°.The water droplets on the Fe2O3/STA FP surface will not drop when the paper turned to vertically position(V?5?L)or rolling over(V?10?L).The experiment also demonstrated that the sample could successfully stick the droplets from the low adhesion superhydrophobic surface.In addition,the damaged Fe2O3/STA FP surface could be repaired simply by impregnation method,the SEM and wetting properties of the repaired samples were measured.The experimental results showed that the damaged filter paper surface has been recovered the superhydrophobic properties after repairing.2.The hydrophobic HMDS-SiO2 nanoparticles were synthesized by SiO2 nanoparticles and modified with hexamethyl disilylamine(HMDS).The flame retardancy and superhydrophobic CS/PA/HMDS-SiO2 CF cotton was fabricated by the simple immersion method and then deposited the hydrophobic HMDS-SiO2 nanoparticles on it.The flame retardant layer composed with the chitosan(CS)and the phytic acid(PA).The surface structure and composition of the textile were studied by the SEM,IR,XPS,XRD and TG tests.The wettability property test showed the modified cotton sample is superhydrophobic surfaces,and the WCA is the 150°±2°;the rolling angle(SA)is 5°.In addition,the experiments of the self-cleaning performance,delaying freeze resistance,acid and alkali corrosion and the WCA changed with the environmental temperature test were carried out.The flame retardant performance of the sample was tested by the vertical combustion experiment.3.The conductive and superhydrophobic recycled papers were prepared with the waste printed papers,the green,non-toxic Kochin Black(KB),ammonium polyphosphate(APP)mixture,with modified the polydimethylsiloxane(PDMS)as hydrophobic agent.By changing the doping amount of KB and APP,a series of KB/APP/PDMS recycled papers were prepared.The electrical conductivity and water contact angles of the samples were detected.Experimental results show that the electrical conductivity of the papers increased with the percentage composition of KB,and these samples have superhydrophobic surfaces which the WCA was irrelevant to it.As an example,the KB0.25/APP0.25/PDMS recycled paper(5#sample)was tested the surface structure and composition by the SEM,IR,XPS,XRD and TG test.And the conductivity,the wettability and the combustion performance of the 5#sample were measured with Four-probe resistivity tester,Contact angle meter and Horizontal and vertical combustion tester.These performances of modified samples were also tested to compare with the blank sample.The results showed that the 5#sample was endowed with electrical conductivity and superhydrophobic property.And it had certain flame retardant performance compared with the blank sample.The KB0.25/APP0.25/PA/PDMS recycled paper(10#sample)was obtained from doping the phytic acid(PA)in the 5#sample to further improve the flame retardant performance of recycled paper.The wettability and combustion performance of the 10#sample was tested.4.The controllable UV light responsive and superhydrophobic cotton samples were fabricated with hydrophobic titanium dioxide(TiO2)P25 and nano-alumina(Al2O3)particles which modified with nontoxic,cheap stearic acid(STA).The five kinds of cotton samples were obtained by adjusting the blending ratio of TiO2/Al2O3.The static water contact angles test showed all cottons were superhydrophobic surfaces,and the WCAs were greater than150°.After ultraviolet(UV)irradiation or heating,the samples displayed the different wettability changes.The wettability of samples showed different responsiveness to UV light,including:superhydrophobic/superhydrophilic,superhydrophobic/hydrophilic,superhydrophobic/hydrophobic,superhydrophobic/superhydrophobic.TiO2/STA(1#sample)could transform the superhydrophobic surface to superhydrophilic materials when received the UV irradiation,and then switched the wettability after heating in the oven.The morphology and structure of five kind samples were detected by SEM,IR,XPS,XRD tests.The sample 1#were applied in the oil/water separation experiment due to it switched the wettability under the UV irradiation or heating.Oil-water separation test revealed that the 1#sample with superhydrophobic surface could separate the crude oil from the water,and the 1#sample after UV irradiation detached the light oil from the water.The separation efficiency and liquid flux of sample were more than 90%and 20000m3/(m2·h)after repeated recycle. |
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