Kinetics of the surfactant‐free emulsion polymerisation of styrene: Application of quantitative theories to the post nucleation stage

Chainey, M.; Hearn, J.; Wilkinson, M. C.

doi:10.1002/pola.1987.080250206

Cited by 25 publications

(15 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values obtained were two orders of magnitude lower than in conventional emulsion polymerizations (22,231. The same order of magnitude for Np has been reported in other soapless emulsion polymerizations (3,20,24). I t is also observed in the figure that the particle number density remained almost constant up to about 20 to 30 percent conversion and then decreased with increasing conversion.…”

Section: Particle Number Densitysupporting

confidence: 85%

Study on soapless emulsion copolymerization methyl methacrylate and n‐butyl acrylate

Pan

Kuo

Chen

1991

Polymer Engineering & Sci

View full text Add to dashboard Cite

The soapless emulsion copolymerization of methyl methacrylate (MMA) and n‐butyl acrylate (n‐BuA) at four levels of monomer feed composition (f10) was studied. Conversion (X), average particle diameter (Dp), molecular weight distribution (MWD), surface charge density, and glass transition temperature (Tg) of the copolymer as a function of reaction time (t) were measured. The copolymers obtained even at low conversion, except for the run of (f10) = 90 wt. percent MMA, exhibit two Tgs in their DSC thermograms. Phase separation is found to occur in the latex particles during polymerization. The heterogeneous distribution of monomers in particles, in which a relatively rich MMA region exists in the shell and a relatively rich n‐BuA region exists in the core of the particles, is assumed to arise from phase separation. The average copolymer composition and the fraction of the two domains are estimated. The polymerizatrion course and particle size growth follow the linear X vs. t2 and Dp3/2 vs. t relationships, respectively. Although the coagulation of particles happens after around 30 percent conversion, the polymerization behaviors, except for increasing rates, are not affected.

show abstract

Section: Particle Number Densitysupporting

confidence: 85%

Study on soapless emulsion copolymerization methyl methacrylate and n‐butyl acrylate

Pan

Kuo

Chen

1991

Polymer Engineering & Sci

View full text Add to dashboard Cite

show abstract

“…Surfactant-free emulsion polymerization is a useful approach to prepare clean monodisperse spheres. [3][4][5][6] Up to now, the preparation of monodisperse microspheres with emulsion or surfactant-free emulsion polymerization is normally performed in inert gas, [7][8][9][10] and achieved at low solids content, usually not more than 20 wt %. 11 It has been recognized that dissolved oxygen is one of the most common impurities in real systems, which consumes radicals, and can influence the radical entry rate into the particles and micelles.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of monodisperse styrene/methyl methacrylate/acrylic acid latex using surfactant‐free emulsion copolymerization in air

Zhang

Chen

Taha

2009

J of Applied Polymer Sci

View full text Add to dashboard Cite

Monodisperse styrene/methyl methacrylate/acrylic acid (St/MMA/AA) copolymer microspheres have been prepared with surfactant-free emulsion polymerization in air. The presence of oxygen in the system not only caused an induction period but also decreased the average particle size (D p ). However increasing AA concentration ([AA]) gave a reduction in the induction period. The FTIR and NMR analysis of the latex copolymer confirmed that the correlation of the copolymer compositions with the feed compositions was much better at the lower [AA] than at the higher levels. The AA contents of the copolymers obtained in air were much lower than those of the copolymers obtained under N 2 protection.Decreasing [AA] led to decrease in the copolymer molecular weight and broadening of the molecular weight distribution, but the particle size distribution (d/D p ) was unaffected. In addition, the average particle diameter (D p ) was proportional to [AA] -0.255 , and increasing comonomers feed content caused linear increase of D p , and a monodisperse sample with final solids contents up to 34.2 wt % was obtained.

show abstract

“…51,54,[61][62][63][64][65][66][67][68] The initial stage of polymerization involves the formation of water-insoluble polymer chains which collapse to form precursor particles. These precursor particles are too unstable to remain isolated, since they possess only a small number of charged initiator residuals on their surface to stabilize them.…”

Section: 55mentioning

confidence: 99%

Surfactant-free synthesis of sub-100 nm poly(styrene-co-divinylbenzene) nanoparticles by one-step ultrasonic assisted emulsification/polymerization

et al. 2015

View full text Add to dashboard Cite

The synthesis of sub-100 nm polymeric nanoparticles in a surfactant-free form is currently very challenging due to the oil nanoemulsion instability in polar solvents and in the absence of stabilizers. Here we report for the first time the surfactant-free synthesis method of poly(styrene-co-divinylbenzene) nanoparticles in an aqueous environment using ultrasonic radiation. This method involves emulsification of the monomers mixture in water, followed by free-radical polymerization under pulsed or continuous acoustic fields. The local energy produced in water by cavitation effects was sufficient to: (1) generate and stabilize the monomer nanoemulsion due to mechanical forces, and (2) drive the radical polymerization due to the heat generated. The average size of the final polymer nanoparticles obtained depended: (i) inversely on the monomer/water interfacial energy, emulsification power, and (ii) directly on temperature, amount of initiator and monomer solubility. The polymer nanoparticle size distribution and shape was considerably improved upon the addition of a co-polymerizable surfactant.

show abstract

Kinetics of the surfactant‐free emulsion polymerisation of styrene: Application of quantitative theories to the post nucleation stage

Cited by 25 publications

References 22 publications

Study on soapless emulsion copolymerization methyl methacrylate and n‐butyl acrylate

Study on soapless emulsion copolymerization methyl methacrylate and n‐butyl acrylate

Synthesis of monodisperse styrene/methyl methacrylate/acrylic acid latex using surfactant‐free emulsion copolymerization in air

Surfactant-free synthesis of sub-100 nm poly(styrene-co-divinylbenzene) nanoparticles by one-step ultrasonic assisted emulsification/polymerization

Contact Info

Product

Resources

About