Post-synthetic modification polymers

As a consequence of the general chemistry of such a process polyelectrolyte brushes prepared by this technique always require a two-step approach where a neutral brush system is formed in a first step and then charged sites are introduced in a second step. However, one should be aware that such a post-synthetic modification process might lead to additional complications if the transformation is not quantitative or if side reactions occur. For a detailed understanding of the structural behavior of such brushes a homogeneous polymer-analogous transformation throughout the whole brush is a basic requirement. 

In this book we have taken a step forward to address the synthesis design of porous polymers, pre- or post-synthetic modification and functionalization to... 

T. Ratvijitvech, R. Dawson, A. Laybourn, Y. Z. Khimyak, D. J. Adams and A. I. Cooper, Post-synthetic modification of conjugated microporous polymers. Polymer, 2014, 55(1), 321-325. 

Strategies for the Post-synthetic Modification of Porous Polymers... 

In comparison to other polymer membranes, soluble porous networks hold an advantage in gas separations in the form of thin solution-cast films. Linear PIMs are soluble and thus good candidates in this regard. The introduction of triazole groups in PIMs (TZPIMs) by post-synthetic modification favors CO2 uptake and greater selectivity for gas separation. TZPIM membranes exhibit exceptional selective permeation as polymeric membranes for gas mixtures like CO2 and N2. 

A linear polycyclic compound, 4,4 -dimethylbiphenyl (4,4 -DMBP), is an intermediate for making monomer of some advanced polymer materials, but the selective synthesis of 4,4 -DMBP is difficult. In this work, modifications were made on a ZSM-5 zeolite for selective methylation of 4-methybiphenyl (4-MBP) to form 4,4 -DMBP. The use of binder, deposition of basic oxide such as calcium oxide over zeolite internal and external surface can effectively improve the product selectivity. An isomorphous substitution of ZSM-5 framework A1 with Fe by a post-synthetic treatment, coupled with modification of external and internal surface by P or Ca leads to high-performance catalyst with stable activity and superior selectivity for synthesis of 4,4 -DMBP by 4-MBP methylation. 

In this section, we introduce post-synthetic treatments that enable further modification of the physical properties such as the structural, electrical, and optical properties of the as-prepared light-emitting polymer nanostructures. Of the various methods of controlling the intrinsic characteristics of nanostructures, we discuss the electrochemical doping and dedoping process using cyclic voltammetry (CV) and unfocused electron (E)-beam irradiation. Hydrothermal treatment of undoped NPs is presented, which involves application of external pressure and heat to NPs. Finally, we describe hybridization with nanoscale... 

Pre designed framework modification of porous polymers and the insertion of functionalization can be facilitated by pre- or post-synthetic... 

In summary, aliphatic polyesters, already an important class of synthetic degradable polymeric biomaterials, have been taken to unprecedented levels of synthetic diversity and tailoring through the efforts of many research groups in the U.S. and abroad. Some of these have been described in this brief review, with a focus on pendent or graft functionality by polymerization of functionalized lactones, and post-polymerization modification. Future efforts in this area must attempt to connect these synthetic advances to specific applications, through the collaborative efforts of experts in the chemistry, biology, and clinical use of synthetic polymer materials. 

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