Ordered array depends greatly on the stereoregularity

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ordered array depends greatly on the stereoregularity of their pendant groups [3] . In general, atactic-PS are usually amorphous due to their random nature which makes it impossible for polymer chain to stack in a regular fashion. In contrast, the syndio-PS has a regular structure which allows it to crystallize from melt. Initiator efficiency calculation: At 100% conversion: 𝑓 = 𝐌 theoretical 𝐌 experimental The f value for this experiment is 0.646 (70% conversion). Experimental errors might due to the lack of purification of the starting materials including the presence of inhibitors in the monomers and solvent, which slows the rate of reaction.
Conclusions: The polymerizations occurred as expected and the desired reaction product was obtained. This lab demonstrates methods for the metallocene polymerization of styrene. It is determined that the polystyrene obtained from organo-metallic catalyst has syndiotactic stereo-regularity which allows the chain to crystallize. This result agrees with the expected phenomenon based on the theory. Reference: 1. "Metallocene Catalysis Polymerization." Polymer Science Learning Center . Web. 21 Apr. 2012. <;. 2. Rodrigues, A., E. Kirillov, and J. Carpentier. "Group 3 and 4 Single-site Catalysts for Stereospecific Polymerization of Styrene." Coordination Chemistry Reviews 252.18-20 (2008): 2115-136. Print. 3. Po, R. "Synthesis of Syndiotactic Polystyrene: Reaction Mechanisms and Catalysis." Progress in Polymer Science 21.1 (1996): 47-88. Print. 4. "Metallocene as Olefin Polymerization Catalysts: An Introduction." Metallocenes: Introduction . Web. 23 Apr. 2012. <;. 5. Rogers, M. G. "Characterization of Molecular Orientation by Differential Scanning Calorimetry." Journal of Materials Science 26.16 (1991): 4281-284. Print.

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