Amine grafting

Figure 1.29 TEM images of Janus silica nanoparticles (diameter 100 nm) in which the amine grafted area is decorated by gold nanocolloids, the remaining area being functionalized by methyl groups. (Reproduced from ref. 54, with permission.)...

The Michael 1,4-addition of methylene activated compounds to various a,p-unsaturated carbonyl compounds in water was promoted by amines grafted on silica gel by a post-modification method. Since the reaction was carried out in a triphasic system, due to low solubility of organic substrates, internal heating by microwave irradiation (100 W) was exploited. In the model reaction between ethyl 2-oxocyclopentanecarboxylate (52) and 3-buten-2-one (53) (Scheme 3.16), the temperature was ramped for 2 min from room temperature to 80 °C. 

The synthesis of 281 (X = CN) from the same reactants was achieved by ultrasonic irradiation without catalyst (03MI488, 04MI562), and under MW irradiation in the presence of sodium bromide or piperidine under solvent-free conditions (04TL8625, 01MI742) as well as heterogeneous amines grafted on silica such as N,N-diethylamino-propylated silica (06H889). 

Activation for allyl-amine grafting Treatment time 5-60 s... 

Lu W, ScuUey JP, Yuan D, Krishna R, Zhou H (2013) Carbon dioxide capture from air using amine-grafted porous polymer networks. J Phys Chem C 117 4057-4061... 

Song et al. (2012a) prepared blends of PMMA with various functionalized poly (propylene-ethylene) copolymers. Blends were characterized by mechanical, morphological, and adhesion tests. Compatibihty was found to increase in the order of unfunctionalized poly(propylene-ethylene), MA-grafted poly (propylene-ethylene), hydroxy-grafted poly(propylene-ethylene), and secondary amine-grafted poly (propylene-ethylene) which latter species exhibited the best compatibilization efficiency. 

In 1994, Lamb et al. developed a series of cryptand-based anion separators. The biggest advantage of cryptand columns, used in gradient elution mode, is the ability to elute non-polarizable and polarizable anions in the same run, which is very difficult (or even impossible) with latex-agglomerated anion exchangers and aminated grafted polymers. ... 

For carbon dioxide sorption applications, apart from the amine grafting of POFs, other functional groups with different polarities also contribute to the improvement of the carbon dioxide sorption capacity. Combined with the simulations, the isosteric heats of adsorption (Qst) of modified POFs are in the order of -COOH >-(0H)2 NH2 (0113)2 non-functionalized framework. Selecting the optimal reaction route to graft these specific units on POFs is one of the hot directions of the PSM of POFs. 

Amine grafted silicas are promising sorbents for selective adsorption, especially for applications in enviromnental control and catalysis. For example, Lasperas et al. (1997) and Angeletti et al. (1988) used amine function-modified... 

Figure 6.7. FTIR spectra of (A) MCM-48 (showing free and H-bonded hydroxyls on surface) and (B) amine-grafted MCM-48.

Figure 6.8. Adsorption/desorption isothemris of CO2 on (A) amine-grafted MCM-48 and (B) amine-grafted siiica xerogel at room temperature. Open symbois indicate desorption soiid symbois indicate adsorption.

Figure 6.9. Cyclic CO2 adsorption/desorption on amine-grafted MCM-48.

Figure 6.11. Adsorption of CO2 on amine grafted silica with and without water vapor, showing that the amount adsorbed is doubled in the presence of water (Huang et al., 2003).

Acrylic acid-grafted F. carica fibers Amine-grafted com stalks Amine-grafted cotton stalk fibers Citric acid treated walnut shell 3.50 4.00 5.12 2.00 28.90 200.00 129.0 30.99 Lo/j 1104] [117] [128] n oQi... 

Hwang YK, Hong D-Y, Chang J-S et al (2008) Amine grafting on coordinatively unsaturated metal centers of MOFs consequences for catalysis and metal encapsulation. Angew Chem Int Ed 47 4144-4148... 

Figure 22. Chemical structure of amines grafted polyglucuronic acid.

This first encouraging part has led us to develop the amines-grafting onto water-insoluble substrates of cellulose. We headed towards cellulose nanocrystals that are partially oxidized in surface. 

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