Nitroxide-Mediated Controlled Free-Radical Emulsion Polymerization Using a Difunctional Water-Soluble Alkoxyamine Initiator. Toward the Control of Particle Size, Particle Size Distribution, and the Synthesis of Triblock Copolymers

2005 ◽  
Vol 38 (24) ◽  
pp. 9963-9973 ◽  
Author(s):  
Julien Nicolas ◽  
Bernadette Charleux ◽  
Olivier Guerret ◽  
Stéphanie Magnet
Keyword(s):  
Particle Size ◽  
Free Radical ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Emulsion Polymerization ◽  
Triblock Copolymers ◽  
Water Soluble ◽  
Size Particle

Semibatch Seeded Emulsion Polymerization of Acrylic Monomers: Bimodal Particle Size Distribution

1997 ◽  
Vol 34 (7) ◽  
pp. 1221-1236 ◽  
Author(s):  
Chorng-Shyan Chern ◽  
Tseng-Jung Chen ◽  
Shinn-Yih Wu ◽  
Horng-Bin Chu ◽  
Chun-Fu Huang
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Emulsion Polymerization ◽  
Seeded Emulsion Polymerization ◽  
Acrylic Monomers

Effects of Emulsifier Concentration on Nucleation Mode of Emulsion Polymerization of Styrene

2013 ◽  
Vol 395-396 ◽  
pp. 399-402 ◽  
Author(s):  
Li Bao Mei ◽  
Xiao Qin Xiao ◽  
Yong Li ◽  
Yan Lin Sun
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Emulsion Polymerization ◽  
Homogeneous Nucleation ◽  
Particle Number ◽  
Nucleation Mode ◽  
P Fraction ◽  
Emulsifier Concentration

The nucleation mode of emulsion polymerization of styrene under different emulsifier (SDS) concentrations is studied in this paper. Some factors such as conversion, particle number (Np), fraction of coverage, polydispersion index (PDI) and particle size distribution (PSD) of the reactions were investigated. The results show that when [SD is less than its CMC, homogeneous nucleation dominates. But when [SD is more than its CMC, micelle nucleation plays the major role.

scholarly journals Insight into winter haze formation mechanisms based on aerosol hygroscopicity and effective density measurements

2017 ◽  
Author(s):  
Yuanyuan Xie ◽  
Xingnan Ye ◽  
Zhen Ma ◽  
Ye Tao ◽  
Ruyu Wang ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Particle Growth ◽  
Water Soluble ◽  
Effective Density ◽  
Pollution Level ◽  
Formation Mechanisms ◽  
Haze Pollution ◽  
Haze Formation

Abstract. We characterize a representative haze event from a series of periodic particulate matter (PM) episodes that occurred in Shanghai during winter 2014. Particle size distribution, hygroscopicity, and effective density were measured online, along with analysis of water-soluble inorganic ions and single particle mass spectrometry. Regardless of pollution level, the mass ratio of SNA/PM1.0 (sulfate, nitrate, and ammonium) slightly fluctuated around 0.28 over the whole observation, suggesting that both secondary inorganic compounds and carbonaceous aerosols (including soot and organic matter) contributed substantially to the haze formation. Nitrate was the most abundant ionic species during hazy periods, indicating that NOx contributed more to haze formation in Shanghai than did SO2. The calculated PM concentration from particle size distribution displayed a variation pattern similar to that of measured PM1.0 during the representative PM episode, indicating that enhanced pollution level was attributable to the elevated number of larger particles. The number fraction of the near-hydrophobic group increased as the PM episode developed, indicating accumulation of local emissions. Three "banana-shape" particle evolutions were consistent with the rapid increase in PM1.0 mass loading, indicating rapid size growth by condensation of condensable materials was responsible for the severe haze formation. Both hygroscopicity and effective density of the particles increased considerably with growing particle size during the banana-shaped evolutions, indicating that secondary transformation of NOx and SO2 was a major contributor to the particle growth. Our results suggest that the accumulation of gas-phase and particulate pollutants under stagnant meteorological conditions and subsequent rapid particle growth by secondary processes, were primarily responsible for the haze pollution in Shanghai during wintertime.

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