Study On Morphology And Nanocoating Performance Of Rasprberry-like Complex Colloidal Particle Clusters

In this experiment,uniform raspberry-like poly(vinylidene fluoride)/polystyrene(PVDF/PS)complex colloidal particle clusters(CCPCs)with PVDF seed particles protruding outward were fabricated with PVDF latex as seeds and styrene(St)as monomers via soap-free seeded emulsion polymerization following single electron transfer radical polymerization(SET-RP)mechanism.The effects of the monomer/seed feed ratio,polymerization temperature and amount of catalyst copper wire on the morphology of composite particles were investigated.Then we also studied the relationship between particle morphology and the properties of latex nanocoatings containing different structural composite particles.Morphology,internal structure,chemical compositions,the size and size distribution and species and quantity of surface elements of composite particles were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM)fourier transform infrared spectrometer(FTIR)and dynamic light scattering(DLS),X-ray photoelectron spectroscopey(XPS)and energy dispersive spectrometer(EDS),respectively.Moreover,the surface morphology of nanocoatings and its hydrophobicity and anti-UV performance were studied by SEM,contact angle instrument and ultraviolet aging tester,respectively.The results showed that,based on SET-RP mechanism,the St/PVDF feed ratio and the polymerization temperature were key to the formation of uniform raspberry-like complex colloidal particle clusters.When the St/PVDF feed ratio was 2.5 g/0.5 g,the polymerization temperature was 35 ?C and the catalyst copper wire was 1 cm of length(with 1.0 mm of diameter),Janus particles with snowman or dumbbell shape were firstly formed.The different hydrophobicity between the PS and PVDF domains was believed to be the driving force for the self-assembly of in-situ formed PVDF/PS Janus particles.Then the in-situ formed PVDF/PS Janus particles behaved as particle surfactant and the self-assembly process could induce Pickering emulsion polymerization.Finally,uniform raspberry-like CCPCs were obtained.Through the deposited method,the static water contact angle of the latex nanocoating with the obtained raspberry-like CCPCs was 174.3°.Compared to deposition,the static water was 169.6° through spin coating,and it all kept at 150° after UV irradiation for 6 h.Therefore,it is expected to get superhydrophobic and anti-UV functional coatings.