Morphology and grafting in polybutylacrylate‐polystyrene core‐shell emulsion polymerization

Abstract

The morphology of polybutylacrylate–polystyrene (PBA–PS) core‐shell latex particles prepared by seeded emulsion polymerization was investigated as a function of the addition method of styrene (St). The thin layer chromatography/flame ionization detector (TLC–FID) technique was used to characterize the morphology of the core‐shell latexes. It was found that grafting PS to the PBA core occurs during seeded emulsion polymerization. The percentage of grafting depended on the method of addition of St, being greatest for the batch reaction, less for the preswollen batch reaction, and least for the semibatch reaction. Upon aging the PBA core‐polymer migrated out of the latex particles with a low degree of grafting to form dumbellshaped particles, whereas the PBA–PS core‐shell particles with a high degree of grafting remained spherical because of the emulsifying ability of graft copolymer.

Mechanism and grafting reactions in seeded emulsion polymerization with emulsified monomer feeding

“…It is very important to know the polymerization mechanism to make particle design and to control the morphology of latex particles. 1,2 Grafting reactions often occur during the course of core-shell composite particles' production. Many factors can affect the grafting reaction between the core and shell of the particles.…”

Study of particle morphology in polymer emulsions and their minimum film formation temperatures

“…In addition, changing the morphology ofthe latex particles can impart to emulsion polymers excellent physical properties and some specific characteristics. [10][11][12][13][14][15][16] In the current work, polymer emulsions having latex particles of distinct morphology are prepared. Their film-forming mechanism is studied, and the relationship between the MFTs of the polymer emulsions and the morphology of latex particles is also discussed.…”

Factorial experimental design for grafting of vinyl monomers onto natural rubber latex

“…A 2 4 experimental design was used to study the effect of the process variables on grafting efficiency for graft polymerizing St and MMA onto NR latex by using redox initiator system. The conversion increased rapidly at the beginning to reach a plateau level.…”

“…The values obtained for grafting efficiency for the 16 experiments of the 2 4 factorial design is shown in column 5 of Table II. From these results, the highest grafting efficiency was (75.79%), obtained in the experiment GNR16.…”

“…Process variables were varied according for a full 2 4 factorial design used to study the effects of reaction temperature (TEMP), rubber-to-monomers ratio (R/ M), St-to-MMA ratio (St/MMA), and initiator amount (INI) on grafting efficiency (GE). The coding of the experimental levels is shown in Table I.…”