Design,preparation And Applications Of Biomass Trans-Anethole Based Polymer Particles

In the last few decades,biobased polymer particles are of particular interest due to their distinctive functions,novel properties,and significant applications in the field of microencapsulation,drug delivery and release,adsorption,catalysis,etc.These polymer particles are generally prepared by several techniques,including hard templating method,self-assembly,suspension polymerization,precipitation polymerization,emulsion polymerization,etc.Here in our work,we prepared the biobased hollow polymer particles from widely available biomass biophenylpropene derived trans-anethole(ANE)and maleic anhydride(MAH)and then studied their potential applications.In the first part of our scientific work,a novel type of hollow polymer particles containing carboxyl groups were prepared from a widely available biophenylpropene trans-anethole(ANE).To prepare the hollow particles,we first prepared polymeric particles using monomers vinyl acetate and maleic anhydride(MAH);and then such particles were taken as sacrificial templates for the subsequent formation of core/shell particles,which were synthesized by using ANE and MAH as co-monomers and divinyl benzene(DVB)as cross-linking agent through precipitation polymerization.After removing the core in the prepared core/shell particles,we obtained hollow particles and then hydrolyzed the anhydride groups into carboxyl functional groups.The hollow particles were characterized by SEM,TEM,and FTIR,and further used as adsorbents.The maximum adsorption towards Cu2+ and methylene blue reached 270 and 940 mg/g,respectively.The recycling studies show that the biobased hollow particles can be easily restored and reused.The hollow particles may find practical applications as sustainable adsorbents.In the second part of our scientific work,a novel type of biobased magnetic hollow particles(BMHPs)were derived from trans-anethole(ANE).To prepare BMHPs,at first,biobased hydrolyzed hollow polymer particles were prepared from ANE according to our first part(Chapter 2)which were then grafted with amino-modified Fe3O4 NPs(Nanoparticles).The prepared BMHPs were characterized by SEM,TEM,XRD,VSM,EDS and FT-IR techniques and further used as bio-adsorbent.The maximum adsorption capacity towards Cr3+,Pb+2 and Rhodamine B was up to 44.5,48.8 and 50.4 mg/g,respectively.Kinetic and isothermal studies show that the adsorption is best fitted with pseudo-second order model and Langmuir isothermal adsorption.BMHPs demonstrated remarkable magneticity and can be easily separated by external magnet.Recycling study shows that the dye-adsorbed BMHPs can be easily restored in HCI/THF mixed solution and reused.The advantages of the new adsorbents,namely,derivative from bio-resource,high adsorption capacity,much ease in separation and regeneration recyclability,render them with promising potentials in wastewater treatment.In the third part of my dissertation,a new type of optically active biobased hollow polymer particles(OABHPs)starting from trans-anethole(ANE).To prepare the OABHPs,ANE and maleic anhydride(MAH)underwent precipitation copolymerization in the presence of particulate template as cores,thereby forming core/shell particles.Subsequently removing the cores provided hollow particles,which were then chiralized with chiral agents,R-and S-1-phenylethylamine;and R-and S-cyclohexyalethylamine,to fabricate the designed OABHPs.The as-prepared particles were characterized by SEM,TEM,elemental analysis,CD,and FT-IR measurements.The chiral particles' enantio-selectivity was further explored by using them as chiral adsorbent towards D-and L-alanine and(-)-cinchonidine and(+)-cinchonine.The optically active hollow particles showed good enantiomeric excess(e.e.)towards racemic alanine.The study not only opens up a new approach for preparing chiral polymer materials,but also provides a versatile platform for making a full use of biomass to develop advanced functional materials.In the fourth part of our scientific contribution,a novel strategy is developed to immobilize cellulase enzyme.Firstly,biobased hollow polymer particles were prepared from ANE through a preparation process established earlier by us(Chapters 2,3),then onto which amino-modified Fe3O4 NPs were covalently attached to form biobased magnetic hollow particles(BMHPs),Further,the surface of BMHPs was modified with glutaraldehyde via Schiff base reaction to produce multi-layered magnetic hollow particles(MMHPs).Cellulase(Aspergillus niger)was covalently immobilized on MMHPs also through Schiff base reaction,providing multi-layered magnetic hollow particles containing cellulase(c-MMHPs).An optimum loading amount of cellulase was achieved as 180 mg/g.The c-MMHPs were characterized by SEM,TEM,EDX,VSM,FT-IR,and XRD analysis techniques.The immobilized cellulase(c-MMHPs)was used as bio-catalyst towards carboxymethyl cellulose(CMC)and showed remarkable catalytic activity and significantly enhanced stability against pH and temperature.Besides,the adsorption ability and the adsorption kinetic study of c-MMHPs towards BSA and methylene blue(MB)dye were also investigated.The maximum adsorption towards BSA protein and MB was found to be up to 716 and 264 mg/g,respectively.Accordingly,the present work opens up a new strategy to immobilize enzymes,and the created MMHPs constitute a promising platform for immobilizing enzymes and even other biomacromolecules.