Surface-polymerized polymer modification

The surface of polymer particles obtained by emulsion polymerization is occupied by emulsifier molecules, initiator fragments, and hydrophilic comonomer units. Therefore, desirable design of the surface ought to be done by choosing the emulsifier, initiator, and comonomer. Some of them are employed in aiming for postreaction at the surface to convert it into a functional one. When any change is necessary on the particle surface, modification of surface can be done by the following means ... 

As mentioned, polymer hybrids based on POs are effective as a compati-bilizer between the olefinic materials and polar ones. Furthermore, some polymer hybrids, such as PP-g-PMMA, etc., show good mechanical strength as polymer materials. On the other hand, surface modification of the molded polymer is one of the most attractive methods to let polyolefin materials functionalize. In this sense, surface polymerization of functional monomers on polyolefins is an important subject for polyolefin hybrids. As previously referred to, the growth of PS on PP via the RAFT process has been reported [92]. 

The methods available for the polymer modification of surfaces are quite varied and we now briefly review each in turn, starting with those methods suitable for use with preformed polymeric materials. One advantage of using such preformed materials is that they can be purified and well characterized, in terms of linkage isomerism, molecular weight distribution etc, before they are applied to the sensor surface. 

The previously discussed principles of grafting-to and grafting-from can also be applied for the modification of polymer surfaces with polymer brushes. However, the binding of linkers and polymerization initiators to polymer surfaces is not as straightforward as it is for oxidic inorganic materials. Thus, dedicated pretreatments are usually necessary. These may include rather harsh reaction conditions due to the chemical inertness of many polymers (see Chapter 3). Alternatively, radiation treatment of polymers (to form radicals) followed by exposure to air may be used to form peroxides and hydroperoxides, which can be directly used as initiators for thermally or ultraviolet-induced graft polymerizations [16,17] (see Chapter 2). 

Adhesion interactions at the solids/polymers interfaces are first and foremost adsorption interactions between the sofid surface and polymer molecules [1—11]. After polymerization there is a low molecular-weight fraction of coupling agents, which can decrease the cohesion and adhesion of the polymer film. If the molecules from this fraction interact with the filler particles preferentially (which can be reached due to the filler surface modification) instead of with the material surface covered, then the boundary layer of the film can be free from this fraction and adhesion increases as strengthening the boundary layer of the coating leads to stronger adhesion of the coating to the covered surfaces [46]. 

The same is true for other polymer modification reactions with acrylamide derivatives especially cationic structures for the formation of cationic surface layers. Furthermore acrylamide derivates like methylenediacrylamide are used in various polymerisation reactions and have to be determined in polymer solutions. The polycations formed by a radical polymerization and their reaction products with polyanions (symplexes) have to be characterized when they are used in polymer modification or other fields. 

In the present text we attempt to do justice to the different topics of polymers and their uses. This text is generally suitable for researchers rather than students. The first chapter of this book discussed sorption mechanism of organic compound in the nanopore of syndiotactic polystyrene crystal. In the second chapter, a discussion was done to illustrate a physico-chemical characterization and processing of pulse seeds. The chemo-enzymatic polymerization for peptide polymers were illustrated in the third chapter. In the fourth chapter, an electrokinetic potential method was used to characterize the surface properties of polymer foils and their modifications. Also, an emulsion polymerizations was discussed in the fifth chapter. Nonconventional methods of polymer surface patterning, polymer characterization using atomic force microscope, biopolymers in the environment, and carbon nanostructure and their properties and applications were discussed in the sixth, seventh, eighth and ninth chapters respectively. Finally, let us point that although many books in the field of pol)nner science appear, none of them are complementary. 

J) Polymer modification area through in-situ polymerizations, side group modifications, or surface modifications via grafting or coatings, is expected to grow, opening new paths for producing microstructured composite or hybrid materials. 

Colloid Polymer Science 211, Nos.2-3, Feb.-March 1999, p.136-44 POLYMER MODIFICATION OF COLLOIDAL PARTICLES BY SPONTANEOUS POLYMERIZATION OF SURFACE ACTIVE MONOMERS... 

K. Yoshinaga, F. Nakashima, T. Nishi, Polymer modification of colloidal particles by spontaneous polymerization of surface-active monomers, Cdloid Pdym. Sd. 1999, 277,136-144. 

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