Surfaced functionalised

When scaling a conventional centimetre-sized reactor down to the micron scale, the surface-to-volume ratio significantly increases to the point where the container walls can effectively become an active or influential part of the reaction or process occurring in the fluidic channel. Clearly this attribute of micro-reactors can be viewed in a positive way and leads to the opportunity of exploiting surface-dependent performance including electrokinetic driven flow, surface functionalisation and mass transfer, and heat transfer. 

Figure 4.28 Some possibilities of surface functionalisation by modified nanosols. (Reproduced from ref. 25, with permission.)...

Determination of the exact mechanism leading to cellular internalisation of CNTs is considered very important in their development as components of biomedical devices and therapeutics intended for implantation or administration to patients. One of the most important parameters in all such studies is the type of nanotubes used, determined by the process by which they are made biocompatible. Interactions with cells have to be performed using biocompatible CNTs, achieved by either covalent or noncovalent surface functionalisation that results in water-dispersible CNTs. A variety of different functionalisation strategies for CNTs have been reported by different groups, therefore direct comparisons are often hampered by the inability to correlate experimental conditions. 

Surface functionalisation of PE with succinic anhydride followed by derivatisation via ring opening reaction yielded surfaces with different functional groups [128]. The PE films were photochemically grafted with maleic anhydride in vapour phase in a reaction involving benzophenone and acetone at 60 °C for 5 h under UV irradiation with a 400 W mercury vapour lamp. The chemical transformation of PE film bearing succinic anhydride group is schematically presented in Scheme 8. 

Recently, we have investigated the MCM-41 surface functionalisation with a new chiral tetrazamacrocycle we prepared in order to synthesise another Mn (II) complex able to perform enantioselective epoxidation (scheme 9)42. 

Fig. 4.4. Preparation of a silica gel surface functionalised with pairs of amino groups at a definite distance apart. The distance between the groups (about 0.70 nm) is fixed by using biphenyl-4,4 -dialdehyde as the template [4,86].

Surface-functionalised gels were also prepared by Wulff et al. using diimine silane monomers [37]. The researchers were interested in isolating the effect of functional group positioning in molecularly imprinted materials. By using a... 

Monoterpenes are widely used in the pharmaceutical, cosmetic and food industry as active components of drugs and ingredients of artificial flavours and fragrances [1]. Camphene is converted to isobomeol and bomeol that are used in formulation of soaps, cosmetic perfumes and medicines, as well as in the industrial production of camphor [2], which is used as an odorant/flavorant in pharmaceutical, household and industrial products [7]. Traditionally, homogeneous catalysts, e.g sulphuric acid, are used, but the effluent disposal leads to environmental problems and economical inconveniences. These problems can be overcome by the use of solid acid catalysts. USY zeolite [3], heteropolyacids [4,5] and sulfonic acid surface-functionalised silica [6] have also been used for the camphene hydration. 

Lisboa P, Gilliland D, Ceccone G, Valsesia A, Rossi F. Surface functionalisation of polypyrrole films using UV light induced radical activation. Appl Surf Sci 2006 252(13) 4397—401. 

A completely different strategy for the surface functionalisation of CNTs with nitrogen-containing groups is the treatment of CNTs under atomic nitrogen flow obtained by molecular nitrogen dissociation in an Ar -t N2 microwave plasma. X-ray photoelectron spectroscopy of the nanotube surface demonstrated the presence of amides, oximes and mainly amine and nitrile groups. ... 

Mesoporous solids provide well-ordered scalfolds for chemistry based largely on surface functionalisation. This is readily achieved at the internal surfaces because of the large numbers of silanol hydroxyls that are present there, and which can be used to attach ligands via established synthetic procedures. 

P. Lisboa, D. Gilliland, G. Ceceone, A. Valsesia, F. Rossi, Surface functionalisation of polypyrrole films using UV light indueed radieal aetivation. Appl. Surf. Sci. 252,4397-4401 (2006)... 

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