Research On Preparation And Products Of Microcrystalline Cellulose

Taking cotton linter as raw material and preparing by adopting microcrystalline cellulose hydrolysis method,this study discusses the adsorptive property of microcrystalline cellulose as well as the technique of using microcrystalline cellulose filled polypropylene to prepare composite material.Meanwhile,by changing conditions such as hydrochloric acid concentration,reaction temperature,response time and ratio of sulfuric acid etc.,the influence of hydrolysis technology on degree of polymerization is studied,cellulose's average degree of polymerization is measured using viscosity method and microcrystalline cellulose is characterized using polarizing microscope,infrared spectrum,X-ray diffraction and laser particle analyzer;by changing adsorption conditions such as PH,adsorption time and adsorbent temperature etc.,this research discusses the adsorption rate of prepared microcrystalline cellulose for phenol and chromium;by changing the filler content of microcrystalline cellulose as well as the category and dosage of dispersing agent and coupling agent,this research discusses the mechanical properties of composite material prepared by using microcrystalline cellulose filled polypropylene and analyzes the tensile fracture surface of composite material using scanning electron microscope.The research results prove that:1 ? When cellulose is hydrolyzed,hydrolysis time,ratio of sulfuric acid,hydrochloric acid concentration and hydrolysis temperature all have influence on cellulose's degree of polymerization,among which hydrochloric acid concentration and reaction temperature have a more obvious influence.When hydrochloric acid concentration is 10%,reaction temperature is 80?,reaction time is 90 mins and ratio of sulfuric acid is 1:20,microcrystalline cellulose's average degree of polymerization obtained reaches minimum(163)and its average particle size is 39 ?m.2?Soak microcrystalline cellulose with sodium hydroxide and petroleum ether,and it can be observed through polarizing microscope that the number of “hot spot” on microcrystalline cellulose soaked by sodium hydroxide decreases,which indicates swelling.When it is dry,the “hot spots” recur,which indicates the disappearance of swelling.After soaking treatment using petroleum ether,its influence on the swelling of microcrystalline cellulose is not obvious.3?By conducting infrared spectroscopic analysis,it can be seen that there are characteristic peaks of microcrystalline cellulose at 1428 cm-1?1025cm-1?1060cm-1?897cm-1.Then,by conducting analysis using XRD,it can be observed that there is strong diffraction peak when 2? is 15°,17°,23°,which shows that the crystallizing type of the prepared microcrystalline cellulose is I crystallographic structure.4?Explore the adsorption property of microcrystalline cellulose using constant temperature bath oscillation method.When PH is 7 and adsorption time is 4 hours,the adsorption rate for phenol reaches the maximum(42%)and adsorption achieves a balance;temperature has little influence on absorbing phenol;swelled microcrystalline cellulose shows an improved effect on phenol and adsorption quantity obviously increases.When PH is 7 and absorption time is 60 mins,adsorption rate for chromium reach the maximum(74%),adsorption achieves a balance and temperature has little influence on absorption.5? Blend microcrystalline cellulose with polypropylene melt to prepare composite material.50% microcrystalline cellulose can be filled in polypropylene,which can be well dispersed in polypropylene when filler content is 10%;when 3% PVA and 1.5% silane coupling agent are added,the mechanical property of composite material is good,tensile strength is 47.7MPa and impact strength is 1.24MJ/m2;aluminic acid ester coupling agent does not have obvious effect.