Firstly, into a 250 ml four-necked round-bottom flask fitted with a mechanical overhead stirrer, coupled with a condenser, drop funnel, different content of MLCB (relative to the weight of styrene monomer) that dispersed in 50 ml deionized water by ultrasonic was introduced into the flask, and a certain dosage of PVA was added, then the system was heated to 92 [degrees] C.
When MLCB was homogeneously dispersed in the suspending medium, the stirrer speed was turned up to 440 rpm, and the system was heated to 85 [degrees] C gradually.
The particle sizes of MLCB in the presence of different PVA dosage were measured by dynamic light scattering (DLS) with a Malven zetasizer 3000 HSA particle sizer.
Effect of the PVA Dosage on the Mean Size of MLCB To systematically investigate the effect of the PVA dosage on the mean size of MLCB, the MLCB amount was fixed at 0.
In addition, we had synthesized a series of PS/MLCB composite particles with different MLCB content in the absence of PVA in our previous report (34).
3c showed the relationship between the MLCB content and optimum PVA dosage, the PVA dosage decreased with the increase of MLCB content.
To further elucidate the effect of PVA dosage on the macromorphology and black luster of resultant PS/MLCB composite particles, a series of experiments were carried out at a given MLCB content of 0.
4, it's concluded that further increase of PVA dosage would result in the deterioration of surface morphology and black luster, which was ascribed to the interaction between the MLCB and PVA, and the interaction became stronger with the increasing dosage of PVA.
To investigate the effect of MLCB on the thermal stability of the resultant PS/MLCB in the present of PVA, TGA measurement was thus employed.
On the one hand, the presence of PVA could eliminate or weaken the inhibition phenomenon of MLCB during the suspension polymerization of styrene, thus the total reactive sites that CB provided increased with the rise in the MLCB content, which could reduce the probability of the chain termination of polymerized macromolecular chain.
A major issue in achieving the ideal PS/MLCB composites was to disperse MLCB particles within the matrix of PS homogeneously.
To improve the dispersion of LCB in aqueous solution, LCB was pretreated by means of SDBS, by which SDBS was adsorbed onto the surface or into pores of LCB, and the hydrophilic and oleophilic features of MLCB were improved.