Olefinic homo- and copolymers including polystyrene, polybutadi- ene, polyisoprene and polystyrene-polybutadiene di-block coplymers are widely used commercial products and most of them can be prepared from anion polymerization. During the last step of the anionic co- and homo- polymerizations, different terminating agents were used to terminate the polymerization and to generate products containing various inorganic salts, which have profound effects on the transparency of the final polymers. For example, polymers containing lithium chloride (LiCl) are generally opaque in appearance while polymers containing lithium methoxide (Li(OCH3)) or lithium hydroxide (LiOH) are transparency.
This study concerns the effect of the inorganic salts on the polymers¡¦ transparency. Inorganic salts such as LiCl, zinc chloride (ZnCl2), alumi- num chloride (AlCl3) were added to the polymer solution to prepare various salt/polymer solution for the study of their transparency, solution viscosity, light scattering and morphology of the solid product after solvent removal. Basically, LiCl will complex with tetrahydrofuran (THF, as activator for anionic polymerization) and the resulting complex were encompassed by the polymer coil in the solution and further aggregation occurred form particle large enough to scatter light. Size of the salt/polymer aggregates was determined by the polymer concentration, salt content, amounts of THF and the solvent applied. The large the particle size, the immense the light scattered and therefore, the reduced transparency of the salt/polymer solution and the resulting solid product after solvent removal. Particle size formed during the termination step is the key factor determining the transparency of the final solid polymers.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0806103-195511 |
| Date | 06 August 2003 |
| Creators | Zhan, Gong-Xi |
| Contributors | none, none, none, Jin-Long Hong, none, none |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0806103-195511 |
| Rights | not_available, Copyright information available at source archive |
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