A highly efficient process of synthesizing a cardanol‐bonded cellulose thermoplastic has been developed by using isocyanate‐modified cardanol. As recently shown by us, the thermoplastic consisting of cellulose diacetate (CDA) and cardanol extracted from cashew nutshells performed high practical properties such as bending strength, heat resistance and water resistance. However, its synthesis process by esterification using acid chlorides of cardanol in a solvent as a common procedure, required high energy consumption by using a large amount of poor solvent to isolate the resulting product from the solvent. Using an isocyanate‐modified cardanol, 3‐pentadecylcyclohexyl (6‐isocyanatohexyl) carbamate (PICC) greatly improved the productivity of the modified cardanol‐bonded CDA (PICC‐bonded CDA). After bonding PICC to CDA in a solvent, the remaining PICC coagulated and was easily removed by filtration, which resulted in remarkably simplifying the separation process of the product. The resulting PICC‐bonded CDA showed insufficient thermoplasticity due to its high interaction between PICC parts. Additional bonding propionyl group improved the thermoplasticity while maintaining good thermal and mechanical properties. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1578–1587, 2013

A new bifuntional ligand, Diammonium 1,4,10,13-tetraoxa-7,16-diazacycrooctadecane-bis(N-carbodithioate), has been synthesized. The UV-spectra of Ni(II)-chelate of the ligand was changed by addition of Na+, K+, Rb+, Cs+ and Mg2+. The composition of Pb(II)-chelate was changed from 1:1 (metal:ligand) to 1:2 by addition of Na+, K+, Cs+, Mg2+, Ca2+ and Sr2+. These changes were produced by the change in the conformation of the diaza-crown ring in the ligand.

The separation and determination of metal ions has been one of the most important topics in analytical chemistry. Developing highly functional chelating agents has been a great concern of many analytical chemists. Investigations for developing new types of chelating agents have produced many highly functional chelating agents having high selectivity and/or sensitivity. [1][2][3][4][5][6] Nowadays, the concepts of chelating agent design have been expanded for not only coordination bonding, but also molecular recognition by a host-guest interaction. [7][8][9][10][11][12][13][14][15] The establishment of molecular recognition was achieved along with the development of inclusion compounds, such as crown compounds, calixarenes, and cyclams. The attractive properties of inclusion compounds have encouraged their vigorous development by analytical chemists. Analytical investigations have proved their potential in analytical chemistry. [13][14][15][16][17][18][19][20] For example, a modification of crown ethers, i.e. the introduction of a side chain into a crown ring, has already been investigated for improving crown-ring selectivity and stimulating new chromoionophore development. introduced bulky groups as "block" subunits into crown compounds to improve their recognition ability for alkali metal ion or ammonium ion as ionophores of ion-selective electrodes. Takagi et al.7-9 combined a crown ether and a chromophore to synthesize a chromoionophore for alkali-metal ions or alkaline earth-metal ions.Our attempted description in this paper introduces a new concept to the design of a chelating agent. We directly combined a diazacrown ring and chelating groups in one molecule, and tried to produce some new functions from it. The direct combination of both functional groups might cause some interaction between them, which might produce new functions. For this purpose, we synthesized two new chelating agents of azacrown compounds, as illustrated in Scheme 1. We believed that our concept of active interaction between a diazacrown ring and functional groups is quite different from studies involving modifications of crown ethers which have so far been investigated.In our previous work, 21 we found that the UV-VIS absorption spectra of the Ni(II) chelates of diammonium 1,4,10, 13-tetraoxa-7,16-diazacycrooctadecane-N,N′-bis(carbodithioate) (DA18CC) and the composition ratio of the Pb(II) chelate of DA18CC were changed by the addition of alkali-metal salts or alkaline earth-metal salts. We deduced that any changes in the absorption spectra and composition ratio were due to an alteration of the steric orientation of two carbodithioate groups along with a conformation change through the coordination of an alkali metal ion into diazacrown ring of DA18CC. This paper systematically considers the spectrophotometric properties of heavy-metal chelates of DA18CC and diammonium 1,4,10-trioxa-7,13-diazacycropentadecane-N,N′-bis(carbodithioate) (DA15CC) in the presence of an alkali-metal ion or an alkaline earth-metal ion. It also discusses th...

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