Preparation And Applications Of Soft-hard Shaped Particles By Multiple Phase Separation Of The Click-disperse Polymerization

Heterogeneous particles refer to particles with uneven and asymmetrical distribution in morphology,composition,structure and properties.At present,there are many methods to prepare special-shaped particles.Among them,seed swelling polymerization phase separation method is more commonly used,but there are still some shortcomings,such as,the preparation is multi-step and time-consuming,a series of reactions are needed for the functionalization of different parts of the particles.For this reason,a pot dispersion polymerization growth particle phase separation method are proposed in our group,which regards the growth particles as a kind of dynamic seed in the dispersion polymerization process.During the polymerization process,the growth particles are going to phase separation and prepares special-shaped particles.Further,in the process of dispersion polymerization,free radical polymerization and click polymerization are combined to make soft-hard shaped particles by using different polymers to phase separation for different hydrophilic and vitrification transition temperature(Tg).On the basis of the above research,this paper uses a pot dispersion polymerization growth particle phase separation method,crosslinking agent are added after the nucleation period,the growth of particles are formed a crosslinked,swellable particle growth regulation,which is a first-time phase,click monomer are then added,which lead to the growth of the secondary-time phase.A multi-part,soft-hard irregular particles are prepare,and the different parts of the particles are functionalized,and a fiurther application modified epoxy resin,so that the soft part are increased tough action,while the hard part are holding strength of epoxy resin.In addition,a crosslinking agent containing double sulfur bond is used to form crosslinked growth particles.Phase degree of crosslinking is come from regulating the swelling and crosslinking degree of growth particles.The core-shell/hollow particles sensitive to glutathione(GSH)are prepared.In this paper,methanol/water(MeOH/H2O=6/4,vol.)was used as dispersion medium,styrene(St)and sodium styrene sulfonate(NaSS)as monomers,and azodiisobutyronitrile(AIBN)as initiator for one-pot dispersion polymerization.The main work of this paper is as follows:1.Preparation of a first-time phase particle:The crosslinking agent Diethylene benzene(DVB)monomer is added at 180 min to produce the core-shell structure particles,and DVB is added at 60 min to produce the snowman particles.Addition time and addition amount of DVB are discussed to better understand the effects of these conditions in terms of particles morphology,structure,surface roughness,composition and size.2.Preparation of the secondary-phase particles:After the DVB reaction 4 h,click monomer trimethylolpropane tris(3-mercaptopropionate)(TMPMP)and l,3,5-triallyl-1,3,-triazine-2,4,6(1H,3H,5H)-trione(the TTT)are added to prepare single concave,multi-concave,single convex or multi-convex soft-hard heterogeneous particles.Addition time and addition amount of DVB,addition time and addition amount of click,and St swelling agent are discussed to better understand the effects of these conditions in terms of particles morphology,structure,surface roughness,composition and size.3.Multi-part particle functionalization:Three methods of different functionalizations of the soft-hard part of the particle.1)Methyl acrylate(GMA)monomer and DVB monomer are added at the same time,the epoxy group is introduced on the hard part of the particle surface.2)The click monomer feeding ratio is adjusted to improve the content of the soft part of the particle.3)After the polymerization,the product particles have a reaction with the functional monomer.The particles surface are introduced functional groups,and analyzed the different functional groups.4.Application of special-shaped particles-toughened epoxy resin:To investigate the effect of particle type and addition amount of particles on mechanical properties and thermal properties of particle/epoxy system.Compared to the E-51 system,in the soft-hard shaped P(St-DVB-GMA-GSH-click)particle(0.004%)/E-51 system,the tensile strength is increased by 33%,the elongation at break is increased by 14%,the modulus is increased by 14%,and the impact strength is increased by 50%.5.Preparation of nuclear-shell/hollow particles by one-step dispersion polymerization:A single dispersed raspberry shaped particle is obtained by using crosslinking agent double(2-methyl propylene)ethyl disulfide(DSDMA)and a one-step feeding dispersion polymerization.Addition time and addition amount of DSDMA,and swelling agent are discussed to better understand the effects of these conditions in terms of particles morphology,structure,surface roughness,and composition.After DSDMA reaction 4 h,the snowman-shaped particles were prepared by adding the click Monomer.The P(St-DSDMA)particles treated by THF are hydrophobic.The hydrophilic P(St-DSDMA-PEG)or P(St-DSDMA-HDT)particles are prepared by adding DSDMA polyethylene glycol(PEG)or 1,6-Hexanedithiol(HDT).THF treated P(St-DSDMA)-shaped particles can degrade in the presence of glutathione(GSH).Photonic crystal membranes are prepared by using a well-dispersed P(St-DSDMA)particle,and the photonic crystal membranes which are assembled from P(St-DSDMA-PEG)particles have the best optical properties,with the highest reflection peaks and the narrowest,reflecting peaks ranging from 650 nm to 750 nm.