Preparation And Properties Of Self-Dispersed Nanoscale Carbon Black

Carbon black（CB）has great application value in textile field due to its excellent coloring,anti-ultraviolet and antistatic properties.However,aqueous CB particulate suspensions easily aggregate and precipitate because of the large specific surface area of the particles,the small size and strong hydrophobic properties manifest together with the van der Waals force which leads to its poor dispersion in aqueous media and thus limits its application.Studies have shown that grafting hydrophilic polymers on CB surface is an effective way to improve the dispersion stability of CB in aqueous systems.In this thesis,we successfully prepared nanoscale CB with good self-dispersing ability by three methods.For the first part,CB was firstly grafted by KH570 using sol-gel method to introduce double bond（C=C）and then the self-dispersed CB/PSSS composites was successfully prepared by KH570-modified CB with p-styrene sulfonate sodium（SSS）via in-situ polymerization.The effects of SSS dosage,APS dosage,and polymerization temperature and polymerization time on the properties of CB/PSSS composite particles were investigated.The result shows that a better preparation process of CB/PSSS is:the mass ratio of SSS to CB is180%,the the mass ratio of APS to SSS is 4%,and polymerization at 75°C for 4 hours.EDS results proved that KH570 and SSS successfully grafted on CB surface,SEM and TEM images showed that the CB/PSSS composite particles exhibited mono-dispersity with core-shell structure.TGA result indicated that the grafting rate of PSSS on CB surface was13.3 wt%.In addition,the prepared CB/PSSS composite particles have good self-dispersing properties in the aqueous phase,with an average particle size of 175.9 nm and Zeta potentials of-38.4 mV.Moreover,the dispersion prepared with CB/PSSS composite has good storage,temperature and centrifugal stability.For the second part,the oxidized CB particles were grafted with MEMO to introduce double bond（C=C）using sol-gel method and further grafted with sodium3-Mercapto-1-propanesulfonate（MPS）via thiol-ene click reaction.to introduce-SO3-onto CB surface,thus successfully prepared self-dispersed CB named CB/MPS-g-MEMO.The effects of the amount of MEMO,amount of ammonia and the ratio of alcohol/water on the contract angle of CB/MEMO were investigated.And the effects of the amount of MPS,reaction time and reaction temperature on the properties of CB/MPS-g-MEMO particles were also investigated.The result shows that a suitable preparation condition of CB/MEMO is the mass ratio of MEMO to oxidized CB is 125%,and the mass ratio of ammonia water to system is 0.34%.A suitable preparation condition of CB/MPS-g-MEMO is the mass ratio of MPS to CB/MEMO is 125%and reacting at 75°C for 4 hours.XPS and Raman spectra prove that MPS was successfully grafted on CB surface and had only a little influence on the internal structure.TGA shows that about 9wt%sulfonated polysiloxane layer was grafted onto the CB surface.SEM and TEM results also indicate that CB/MPS-g-MEMO with smooth surface and have a core-shell structure with a thin polysiloxane layer.The resulting CB/MPS-g-MEMO exhibited excellent self-dispersing ability in co-solvent of NMMO and water aqueous with an average particle size of 166.8 nm,a particle size distribution index of 0.12,and a Zeta potential of up to-41.9 mV.And the prepared CB dispersion possessed high storage,thermal and centrifugal stability.For the last part,CB was firstly grafted by MPTS using sol-gel method to introduce mercapto groups（-SH）and then copolymerized with the water-soluble monomer DMC and the reactive monomer CHPMA through the thiol-ene click reaction.Thus the reactive self-dispersed CB was successfully prepared named CB/P-（DMC-co-CHPMA）-g-MPTS.The effects of different molar ratios of DMC and CHPMA on the properties of CB/P-（DMC-co-CHPMA）-g-MPTS particles and colored cotton fabrics were investigated.A suitable preparation condition for CB/P-（DMC-co-CHPMA）-g-MPTS is 1g CB/MPTS,the molar ratio of DMC and CHPMA is 4:2,the mass ratio of initiator to monomer is 1%,and polymerization is performed at 75°C for 4 hours.XPS results show that MPTS,DMC and CHPMA are successfully grafted onto CB surface.SEM and TEM results show that CB/P-（DMC-co-CHPMA）-g-MPTS has good dispersibility with core-shell structure.The TGA results show that about 21wt%copolymer grafted onto CB surface.The prepared CB/P-（DMC-co-CHPMA）-g-MPTS has good self-dispersing ability in the aqueous phase with an average particle size of 210.1nm,a particle size distribution index of 0.13,and a Zeta potential of up to 31.3mV.The prepared modified CB has good dyeing performance on cotton fabrics.A better dyeing condition is:6%owf CB,20 g/L Na₂CO₃ and the bath ratio is 1:30.