Tailor-made materials, synthesis

It has been demonstrated that ROMP represents a highly versatile tool in the preparation and modification of functional polymer supports. The use of well-defined initiators allows the highly reproducible preparation of tailor-made materials in particular in terms of functionalization. Various polymerization techniques such as precipitation- and graft-polymerization may be applied. In due consequence, the use of suitable polymerizable ligands allows the synthesis of well-defined heterogeneous supports. 

Novel synthesis methods of LHD -based catalysts, opening the new application fields of the tailored-made materials, designed ... 

Thus, a combination of RAFT technology and clay nanotechnology for the synthesis of PCNs by RAFT-mediated polymerization can allow the preparation of tailor-made materials with specific properties for niche applications. 

An important challenge in the design of novel conjugated polymers is the synthesis of materials with tailor-made solid-state electronic properties. This section outlines the synthesis of the most significant classes of poly(para-phenylenevinylene)s (PPVs), poly(para-phenylene)s (PPPs), and related structures. Furthermore, this review demonstrates that the chromophoric and electronic properties of conjugated rr-systems are sensitive to their molecular and supra-molecular architecture. 

Although the word processing is normally reserved for the method of manufacture of any finished article it is important to recognise that the word can also describe the preparation or synthesis of the material. Thus in the polymer field it can range from improved methods of synthesis of polymers with tailor made properties (see Section 5.5) to improved methods of dispersion or improved methods of extrusion. Typical technological uses are shown in Tab. 5.25. 

Structural variants of porphyrins obtained by heterocyclic core modification, macrocyclic ring expansion, alteration of structural topology, and incorporation of tailor-made substituents constitute an area of considerable interest. Potentially rich families of conjugated heteroporphyrins with well-defined structures provide an opportunity for implementation in applications in the field of chemistry, biology, and material science. This chapter reports on the synthesis and structural modifications of a number of heteroporphyrins. 

In addition, significant advances have been made in both basic and applied research which allow a smart and efficient solution to most of these problems. As an example, let us quote the development of the synthesis of novel catalytic materials with tailor-made and more suitable characteristics (stable nanocrystals, controlled hydrophobicity, better thermal and/or mechanical stability, etc.), the understanding of the complex phenomena involved in the catalytic transformation of polar molecules within zeolite micropores or the demonstration that fixed bed reactors, which have many advantages over conventional batch reactors, can be easily used, even for liquid-phase reactions and even for laboratory scale experiments. 

As the shortcomings of the traditional preparative methods outlined above became apparent, it was realized that alternative procedures were required to produce uniform or tailor-made adsorbents and shape-selective catalysts. As we saw in Chapter 11, one major route was opened up by the Linde synthesis in 1956 of the crystalline molecular sieve zeolite A. The search for new microporous crystalline materials has continued unremittingly and has resulted in the synthesis of novel zeolitic structures including the aluminophosphates, which are featured in this chapter. 

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