Aggregation of stereoregular poly(methyl methacrylates)

• Published in: Advances in colloid and interface science Vol. 27; no. 1; pp. 81 - 150
• Main Authors: Spěváček, J., Schneider, B.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.1987; Elsevier
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Properties and characterization; Structure, morphology and analysis; Aggregation; Colloidal gel; Molecular motion; Thermal history; Dilute solution; Methyl methacrylate polymer; Stereospecific polymer; Influence; Kinetics; Bibliography; Concentrated solution
• ISSN: 0001-8686; 1873-3727
• DOI: 10.1016/0001-8686(87)85010-8

In this review, experimental results obtained in studies of aggregation of stereoregular poly(methyl methacrylates) (PMMA) are reviewed and critically evaluated. Besides aggregation in solution, attention is also paid to the corresponding ordered structures in the solid state. Three types of aggregates of stereoregular PMMA are discussed in parallel: 1) the stereocomplex of PMMA formed by the mixing of solutions of isotactic (i) and syndiotactic (s) PMMA; 2) the self-aggregates of s-PMMA; and 3) the self-aggregates of i-PMMA. In the introductory sections, information on the conformational structure and dynamic behavior of stereoregular PMMA in solutions and in the solid state is summarized. In Part IV, the possibilities of various physical methods in obtaining various types of information on PMMA aggregates are demonstrated. With each method, the main results obtained in studies of PMMA aggregates are cited. The problems of the structure of PMMA aggregates are the subject of the following three parts. Information concerning the stoichiometry of the PMMA stereocomplex and the effects of stereoregularity on the formation and thermal stability of stereocomplex aggregates and s-PMMA self-aggregates is discussed in Part V. For these systems in various solvents, the values of the minimum length of s-sequences necessary for aggregation are given. Attention is also paid to the time-course of aggregation and to its various stages. In Part VI, based on the results of NMR and vibrational spectroscopy, it is shown that aggregation of stereoregular PMMA is caused by interactions of ester groups. The backbone conformational structure in PMMA aggregates is also discussed in this chapter; it is shown that the stereoregular sequences assume an approximately tt structure. In Part VII, the effects of aggregation on the mobility and mutual ordering of the chains in aggregates are described. Experimental results indicating that double-helical structures are formed in aggregation of stereoregular PMMA are discussed. Information on some other systems directly related to the aggregation of stereoregular PMMA (including the “replica polymerization” of methyl methacrylate) is summarized in Part VIII.