Cyclodextrin-based nanosponges as drug carriers

• Francesco Trotta,
• Marco Zanetti and
• Roberta Cavalli

Beilstein J. Org. Chem. 2012, 8, 2091–2099, doi:10.3762/bjoc.8.235

• increasing its aqueous solubility, and formed inclusion complexes. FTIR, DSC and XRPD analyses confirmed the drug interaction with nanosponges. Moreover camptothecin loaded in nanosponges was seen to be more effective than the plain drug on HT29 cells. The same formulation was recently shown to be an

• many essential oils and fragrances with a boiling point of 198 °C, was encapsulated in different types of nanosponges as a liquid oil model [43]. β-CD-1/4 nanosponges can incorporate 8% w/w of linalool within their structure. The entrapment of linalool in the nanosponge matrix was confirmed by DSC

Acylsulfonamide safety-catch linker: promise and limitations for solid–phase oligosaccharide synthesis

• Jian Yin,
• Steffen Eller,
• Mayeul Collot and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2012, 8, 2067–2071, doi:10.3762/bjoc.8.232

• generated ester 6 with an overall yield of only 28% [21][22]. In contrast, when commercially available 4-formylcinnamic acid (5) served as starting material, ester 6 was prepared in just two steps and with an increased overall yield of 88% [23]. Reaction of alcohol 6 and disuccinimidyl carbonate (DSC) in

• two novel linkers on different resins. Synthesis of a new acylsulfonamide safety-catch linker. Reagents and conditions: (a) benzaldehyde, Na2SO4, DCM; (b) NaBH4, EtOH; 82% over two steps; (c) H2, 10% Pd/C, EtOH, DIPEA; (d) cat. H2SO4, MeOH, 88% over two steps; (e) DSC, Et3N, DCM/CH3CN, 85%; (f) DHP, p

Polysiloxane ionic liquids as good solvents for β-cyclodextrin-polydimethylsiloxane polyrotaxane structures

• Narcisa Marangoci,
• Rodinel Ardeleanu,
• Laura Ursu,
• Constanta Ibanescu,
• Maricel Danu,
• Mariana Pinteala and
• Bogdan C. Simionescu

Beilstein J. Org. Chem. 2012, 8, 1610–1618, doi:10.3762/bjoc.8.184

• deformation. Various rheological parameters were calculated by using the Rheoplus software. Differential scanning calorimetry (DSC) DSC measurements were conducted on a DSC 200 F3 Maia device (Netzsch, Germany). About 10 mg of each sample was heated in pressed and pierced aluminum crucibles. A heating rate of

• -Im/Br and PDMS-Im/Br+PRot. Flow curves for PDMS-Im/Br and PDMS-Im/Br + PRot at 25 °C. Temperature dependence of flow curves for PDMS-Im/Br ionic liquid. Temperature dependence of flow curves for PDMS-Im/Br+PRot. DSC second heating curves of: (1) PDMS-Im/Br ionic liquid, (2) mixture of PDMS-Im/Br with

Influence of cyclodextrin on the solubility of a classically prepared 2-vinylcyclopropane macromonomer in aqueous solution

• Helmut Ritter,
• Jia Cheng and
• Monir Tabatabai

Beilstein J. Org. Chem. 2012, 8, 1528–1535, doi:10.3762/bjoc.8.173

• DLS was about 4.1 nm. DSC measurement showed the glass-transition temperature (Tg) at about 123.5 °C. Due to the hydrophilicity of the amino end groups of 3 a typical LCST (lower critical solution temperature) was observed close to that of unmodified poly(NiPAAm) at about 33.4 °C (Figure 2). Via

• differential scanning calorimetry (DSC) with a Perkin-Elmer Model DSC-7 in nitrogen atmosphere; about 10 mg samples were used at a scan rate of 15 K/min. Tg was taken as the average of three measurements using the midpoint method. LCST were determined by transmission changes (at 500 nm) of the solutions heated

Synthesis and characterization of low-molecular-weight π-conjugated polymers covered by persilylated β-cyclodextrin

• Aurica Farcas,
• Ana-Maria Resmerita,
• Andreea Stefanache,
• Mihaela Balan and
• Valeria Harabagiu

Beilstein J. Org. Chem. 2012, 8, 1505–1514, doi:10.3762/bjoc.8.170

• chemical structure and the thermal and morphological properties of the resulting polyrotaxane were investigated by using NMR and FT-IR spectroscopy, TGA, DSC and AFM analysis. The encapsulation of BT inside the PS-βCD cavity results in improvements in the solubility, as well as in different surface

• taken into consideration. The thermal stability of the inclusion-complex BTc, PDOF-BT and the PDOF-BTc copolymers was investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), as shown in Figure 5 and Figure 6, and the results are summarized in Table 2. The

• = 7.66 J/g)) compared with non-complexed BT (111 °C). DSC profiles of PDOF-BTc copolymer does not indicate Tg or melting temperature in the 30–200 °C interval, as can be seen in Figure 6. These findings indicated their amorphous nature and rigid chains. The effect of PS-βCD on the thermal stability of

Restructuring polymers via nanoconfinement and subsequent release

• Alan E. Tonelli

Beilstein J. Org. Chem. 2012, 8, 1318–1332, doi:10.3762/bjoc.8.151

• -lactic acid) (PLLA) chains was suspended overnight in a solution containing poly(ε-caprolactone) (PCL), the resulting solid α-CD IC contained included PCL chains, while the displaced PLLA chains had moved into solution. Polymer–CD ICs are readily characterized by FTIR, NMR, DSC, and X-ray observations [6

• distinguished [20]. Finally, examination by DSC can determine whether the guest polymer has been included in the columnar CD lattice or not, by the absence or presence, respectively, of the thermal signature(s) characteristic of the polymer, i.e., Tg and/or Tm. The formation of polymer ICs with host urea (U

• crystallizabilities were also observed for PCLs of various molecular weights when coalesced from their U ICs [68]. Density and DSC measurements [70] revealed a closer packing of chains in the noncrystalline sample regions, but this did not affect the overall crystallinity of the c-PCL films. Increased elastic storage

Design of a novel tryptophan-rich membrane-active antimicrobial peptide from the membrane-proximal region of the HIV glycoprotein, gp41

• Evan F. Haney,
• Leonard T. Nguyen,
• David J. Schibli and
• Hans J. Vogel

Beilstein J. Org. Chem. 2012, 8, 1172–1184, doi:10.3762/bjoc.8.130

• suspensions and the resulting lipid and peptide mixtures were examined by differential scanning calorimetry (DSC) to determine the effect of the peptides on the thermotropic phase behaviour of phospholipids. Eukaryotic membranes typically have a high phosphatidylcholine content, while bacterial membranes are

• explain why gp41w-4R and gp41w-KA readily lyse red blood cells in vitro. The DSC results of the gp41w derivatives mixed with DPPG lipids demonstrate that all the peptides induce changes in the thermotropic phase behaviour of negatively charged lipids. The pretransition at ~33 °C seen in the DSC trace of

• small peak at ~40 °C. The addition of gp41w-KA and gp41w-FKA to DPPG gave remarkably similar DSC results. The main phase transition at 40 °C is abolished in the presence of either peptide and is replaced by a broad transition centered at 47 °C. This could be due to the formation of peptide–lipid

Synthesis and characterization of a novel carboxyl group containing (co)polyimide with sulfur in the polymer backbone

• Miroslav Mrsevic,
• David Düsselberg and
• Claudia Staudt

Beilstein J. Org. Chem. 2012, 8, 776–786, doi:10.3762/bjoc.8.88

• copolymers were characterized by using NMR, FTIR, GPC, and DSC. Furthermore, with regard to processing and potential applications, the thermal stability, solubility in common organic solvents, moisture uptake, and transparency were investigated. Compared to commercially available transparent polymers, i.e

• during the polyaddition reaction. DSC measurements Differential scanning calorimetry (DSC) is a method to characterize the thermal properties of polymers and is also useful in disclosing composition based correlations. In order to do so, the glass-transition temperatures of all (co)polyimides synthesized

• Avance DRX 500 spectrometer with Si(CH3)4 as the internal standard at room temperature in deuterated tetrahydrofuran (THF-d8). FTIR spectra were recorded at 4 cm−1 resolution with 1024 sample scans on a Nicolet 6700 equipped with an ATR unit. DSC measurements were performed on a Mettler Toledo DSC822

Synthesis of 2,6-disubstituted tetrahydroazulene derivatives

• Zakir Hussain,
• Henning Hopf,
• Khurshid Ayub and
• S. Holger Eichhorn

Beilstein J. Org. Chem. 2012, 8, 693–698, doi:10.3762/bjoc.8.77

• established in the present case. Finally, we investigated compounds 9 and 10 under a polarizing microscope for their textural features, and DSC experiments were carried out to determine the phase-transition temperatures. In the case of 9, the first melting-point peak in the DSC never recovered, but a very

• − C8H4O2N]+); HRMS (m/z): [M + Na]+ calcd for C21H19NO4Na, 372.120362; found, 372.120630 + 1.05 ppm. Preparation of carbene adducts 4 [18] and 5. Preparation of the cycloheptatrienes 7 and 8 [18][20]. Preparation of derivatives 9 and 10. Supporting Information Supporting Information File 212: DSC-data of

Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit

• Govindaswamy Shanker,
• Marko Prehm and
• Carsten Tschierske

Beilstein J. Org. Chem. 2012, 8, 472–485, doi:10.3762/bjoc.8.54

• studied by optical polarizing microscopy (PM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). All dimesogens exhibit broad ranges of cybotactic nematic phases (NcybA and NcybC), in some cases accompanied by additional mesophases (CybA or SmC) at lower temperature. The combination of

• differential scanning calorimetry (DSC, DSC-7, Perkin-Elmer). The assignment of the mesophases is based on the combined results of optical textures and X-ray diffraction (XRD) studies. XRD investigations on aligned samples were performed by using a 2D wire detector (HI-Star, Siemens AG). Alignment was achieved

• of a uniaxial mesophase, but surprisingly, no enthalpy change is associated with this transition as observed in the DSC traces (Figure 2a). Similar features can be observed for the shorter homologue CB-Ox/3 (see Table 1). XRD patterns of the nematic phase of compound CB-Ox/4, obtained with a

Discovery of practical production processes for arylsulfur pentafluorides and their higher homologues, bis- and tris(sulfur pentafluorides): Beginning of a new era of “super-trifluoromethyl” arene chemistry and its industry

• Teruo Umemoto,
• Lloyd M. Garrick and
• Norimichi Saito

Beilstein J. Org. Chem. 2012, 8, 461–471, doi:10.3762/bjoc.8.53

• temperatures of 2 could not be determined by a differential scanning calorimeter (DSC), because 2 reacted with the cell materials, i.e., stainless steel and gold, at elevated temperature due to their strongly oxidizing effect on the hexavalent sulfur(VI) element. Many arylsulfur chlorotetrafluorides were

• measured with DSC and these are discussed in Supporting Information File 1. We examined reaction conditions for the conversion of trans-PhSF4Cl (2a) to PhSF5 (3a) with various reactive fluorides using an approximately one-gram scale of 2a, as seen in Table 3. Janzen et al. described in the experimental

Perhydroazulene-based liquid-crystalline materials with smectic phases

• Zakir Hussain,
• Henning Hopf and
• S. Holger Eichhorn

Beilstein J. Org. Chem. 2012, 8, 403–410, doi:10.3762/bjoc.8.44

• several liquid-crystalline phases over a wide temperature range. Variable-temperature optical polarized microscopy (vt-OPM) and differential scanning calorimetry (DSC) measurements revealed that compound 8b is converted into a SmC phase at ~28 °C and converts into a short-temperature-range SmA and N phase

Synthesis and mesomorphic properties of calamitic malonates and cyanoacetates tethered to 4-cyanobiphenyls

• Katharina C. Kress,
• Martin Kaller,
• Kirill V. Axenov,
• Stefan Tussetschläger and
• Sabine Laschat

Beilstein J. Org. Chem. 2012, 8, 371–378, doi:10.3762/bjoc.8.40

• ,b were isolated as colourless solids in 59% and 41% yield. The obtained malonate and cyanoacetic esters 11a,b and 13a,b were subjected to differential scanning calorimetry (DSC) studies (Figure 1, Figure 2, and Table 1). During the first heating runs all compounds did not show the appearance of any

• referenced to an internal Me4Si (TMS) standard. IR: Bruker 22 FT-IR spectrometer with a golden-gate single-reflection diamond ATR system. MS: Bruker Daltonics mikro-TOF-Q (ESIMS). Differential scanning calorimetry (DSC): Mettler-Toledo DSC 822e (heating/cooling rates were 5 or 10 K·min−1). Polarizing optical

• , 7.22; N, 6.69; found: C, 74.04; H, 7.18; N, 6.54; Rf 0.58 (hexanes/EtOAc 2:1). DSC traces of 13a (heating/cooling rate 5 K/min). DSC traces of 11a (heating/cooling rate 10 K/min). Schlieren textures of 11a and 11b under crossed polarizers, upon cooling (cooling rate 5 K/min) from the isotropic liquid

Liquid-crystalline nanoparticles: Hybrid design and mesophase structures

• Gareth L. Nealon,
• Romain Greget,
• Cristina Dominguez,
• Zsuzsanna T. Nagy,
• Daniel Guillon,
• Jean-Louis Gallani and
• Bertrand Donnio

Beilstein J. Org. Chem. 2012, 8, 349–370, doi:10.3762/bjoc.8.39

• such as gel-permeation chromatography (GPC), or through a combination of these methods. Product purity and ligand-grafting rates and ratios can be determined through the use of techniques such as NMR spectroscopy, thermal analysis (DSC/TGA), elemental analysis, and other spectroscopic techniques (e.g

• displayed higher transition temperatures and a wider mesophase range than the free ligand, as determined from DSC and POM experiments. Unfortunately, no phase assignments were made by diffraction methods, precluding the determination of either the supramolecular interactions of the ligands or the positional

Laterally substituted symmetric and nonsymmetric salicylideneimine-based bent-core mesogens

• Sonja Findeisen-Tandel,
• Wolfgang Weissflog,
• Ute Baumeister,
• Gerhard Pelzl,
• H. N. Shreenivasa Murthy and
• Channabasaveshwar V. Yelamaggad

Beilstein J. Org. Chem. 2012, 8, 129–154, doi:10.3762/bjoc.8.15

Improved syntheses of high hole mobility phthalocyanines: A case of steric assistance in the cyclo-oligomerisation of phthalonitriles

• Daniel J. Tate,
• Rémi Anémian,
• Richard J. Bushby,
• Suwat Nanan,
• Stuart L. Warriner and
• and Benjamin J. Whitaker

Beilstein J. Org. Chem. 2012, 8, 120–128, doi:10.3762/bjoc.8.14

• that it provides a simple, high-yielding route to metal-free α-alkylated phthalocyanines. Liquid-crystal properties The liquid-crystal behaviour of the compounds we synthesised was investigated by polarising microscopy, differential scanning calorimetry (DSC) and, in the cases of compounds 7c–7e, by

• low-angle X-ray diffraction. The DSC data is summarised in Table 2, the phase behaviour of the isoalkyl series is compared graphically with that for the n-alkyl series in Figure 1 and typical polarizing micrographs are shown in Figure 2. Compounds 7b and 7c exhibit Colh columnar mesophases. For

• compounds formed in the highest yields (for those phthalonitriles branched at the 3-position of the alkyl chain) are not liquid-crystalline, liquid-crystalline examples with branching at the 3-position could easily be designed. Experimental DSC Studies DSC studies used a Perkin Elmer DSC-7 instrument

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• mainly investigated by Rasmussen et al. [29][81][86][87][88][96][97][98][99]. However, these systems were not intended as nonlinear optical polymers. Their properties were primarily studied by electrochemistry, absorption spectroscopy, NMR, FTIR spectroscopy, DSC, and TGA. Nevertheless, in 1998, Tripathy

Sexithiophenes as efficient luminescence quenchers of quantum dots

• Christopher R. Mason,
• Yang Li,
• Paul O’Brien,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2011, 7, 1722–1731, doi:10.3762/bjoc.7.202

• extraction apparatus) with methanol. The crude product was then collected with chloroform and isolated by precipitation. The product was isolated by column chromatography (silica, toluene) and then precipitation to afford 7a as a red solid (0.47 g, 40%); mp 177 °C (by DSC); 1H NMR (CDCl3) δ 7.27 (m, 2H

• , toluene) and then precipitation to afford 7b as a red solid (0.23 g, 20%); mp 195 °C (by DSC); 1H NMR (CDCl3) δ 7.26 (m, 2H), 7.20 (d, J = 4.0, 2H), 7.15 (d, J = 3.5, 1H), 7.08 (m, 2H), 6.80 (d, J = 3.5, 1H), 3.36 (s, 8H), 2.55 (s, 3H); MS (MALDI-TOF) m/z: 769 (M+, 68%), 767 (M+, 100%); FTIR (KBr) ν/cm−1

Novel carbazole–pyridine copolymers by an economical method: synthesis, spectroscopic and thermochemical studies

• Aamer Saeed,
• Madiha Irfan and
• Shahid Ameen Samra

Beilstein J. Org. Chem. 2011, 7, 638–647, doi:10.3762/bjoc.7.75

• synthesized by a modified Chichibabin reaction, i.e., by the condensation of diacetylated N-alkylcarbazoles with 3-substituted benzaldehydes in the presence of ammonium acetate in refluxing acetic acid. All the polymers were characterized by FTIR, 1H NMR, 13C NMR, UV–vis spectroscopy, fluorimetry, TGA and DSC

• of P2a in THF at room temperature. Thermochemical properties of the polymers The thermal properties of the two series of polymers, P1 and P2 were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). For TGA the samples were heated (PerkinElmer Thermal Analysis

• . For DSC, the samples were first heated to melting, then cooled to the glassy state and reheated to determine the glass transition temperature (Tg). A representative DSC graph is shown for P1a in Figure 5. Tg is calculated from the second heating curve. As it can be seen from the graph, Tg for the

Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor

• Bernhard Gutmann,
• Toma N. Glasnov,
• Tahseen Razzaq,
• Walter Goessler,
• Dominique M. Roberge and
• C. Oliver Kappe

Beilstein J. Org. Chem. 2011, 7, 503–517, doi:10.3762/bjoc.7.59

• 1,5-diphenyltetrazole by about 60 °C [39]. However, in case of the parent tetrazole (CN4H2) itself, differential scanning calorimetry (DSC) experiments suggest that the decomposition onset temperature does not change significantly when the material is contaminated with either Fe or 316 stainless steel

Amphiphilic dendritic peptides: Synthesis and behavior as an organogelator and liquid crystal

• Baoxiang Gao,
• Hongxia Li,
• Defang Xia,
• Sufang Sun and
• Xinwu Ba

Beilstein J. Org. Chem. 2011, 7, 198–203, doi:10.3762/bjoc.7.26

• crystalline behavior Thermotropic behavior of ADPs was investigated by a combination of differential scanning calorimetry (DSC), polarization optical microscopy (POM) and X-ray diffraction (XRD) experiments. Figure 4 shows DSC curves of amphiphilic dendritic peptides. In the DSC scan from −60 °C to 200 °C, G1

• showed three phase transitions at 15 °C, 25 °C and 40 °C, which are attributed to phase transitions of recrystallization and crystal to isotropic melt. G2 only showed a phase transitions at 71 °C, which is attributed to the phase transition of crystal to isotropic melt. DSC analysis of G3 showed phase

• CDCl3 with tetramethylsilane as internal standard unless indicated otherwise. Mass spectra were carried out using MALDI-TOF/TOF matrix assisted laser desorption ionization mass spectrometry with Autoflex III Smartbeam (Bruker Daltonics Inc). Differential scanning calorimetry (DSC) was carried out with a

About the activity and selectivity of less well-known metathesis catalysts during ADMET polymerizations

• Hatice Mutlu,
• Lucas Montero de Espinosa,
• Oĝuz Türünç and
• Michael A. R. Meier

Beilstein J. Org. Chem. 2010, 6, 1149–1158, doi:10.3762/bjoc.6.131

• , the physical properties of the polymers are correspondingly affected. A different insight into the effect of the isomerization ratio on the thermal properties of the polymers can be achieved by differential scanning calorimetry (DSC) analysis of the synthesized polymers. The thermal behavior of two

• polymers with similar Mn, synthesized at same temperature with and without BQ, was studied by DSC (Figure 8). Polymer P12 (Table 1, entry 12), possessing a lower degree of isomerization, exhibited a quite sharp Tm peak at 47 °C. On the other hand, the DSC trace of polymer P11 (Table 1, entry 11), with

• performed relative to PMMA standards (Polymer Standards Service, Mp 1100–981.000 Da). Differential scanning calorimetry (DSC) experiments were carried out under a nitrogen atmosphere at a heating rate of 10 °C × min−1 with a DSC821e (Mettler Toledo) calorimeter up to a temperature of 150 °C with a sample

Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects

• Janja Makarević,
• Milan Jokić,
• Leo Frkanec,
• Vesna Čaplar,
• Nataša Šijaković Vujičić and
• Mladen Žinić

Beilstein J. Org. Chem. 2010, 6, 945–959, doi:10.3762/bjoc.6.106

• ) and diesters (3b, 4b). It appears that the increased hydrogen bonding potential of terminal diamide derivatives provides somewhat more versatile gelators capable of gelating solvents of medium and low polarity where intermolecular hydrogen bonding is favored. TEM and DSC investigations As reported

• thicker fiber bundles. In the toluene gel, (S,R)-1b organizes into wide and short tapes with low networking capacity which is reflected in a very low (Geff 0.15 mL) gelator effectiveness. DSC investigation of the highly efficient (S,R)-1a gelator of water/DMSO solvent mixture showed only one transition in

• dipeptide-CONH2)oxalamides 1c–5c in gelation of various solvents and solvent mixtures (sol.: soluble, ins.: insoluble; cr.: crystalline; [A] gel/sol mixture). ΔH and transition temperatures for selected retropeptide DMSO/water obtained from DSC heating and cooling cycles. Supporting Information Supporting

Formation of epoxide-amine oligo-adducts as OH-functionalized initiators for the ring-opening polymerization of ε-caprolactone

• Julia Theis and
• Helmut Ritter

Beilstein J. Org. Chem. 2010, 6, 938–944, doi:10.3762/bjoc.6.105

• calorimetry (DSC) curve of compound 4 shows a glass transition temperature (Tg) at 63 °C. The low molecular weight epoxide-amine adduct 4 is soluble, e.g., in tetrahydrofuran (THF), methanol, chloroform but insoluble in n-hexane and water. We also carried out the above described one-pot reaction in THF as

• mol−1, respectively which are clearly higher than the values achieved in the one-pot synthesis as described above. The DSC curve of the addition product 4 synthesized via two-pot reaction shows a Tg at 76 °C which is an increase of 7 °C compared with the product obtained via the one-pot synthesis (Tg

• to start this side reaction. The significant increase of molecular weight in comparison with compound 4 was also confirmed by DLS measurements. As shown in Figure 6, the number-average hydrodynamic diameter increases after grafting from 1.45 nm (4) to 3.33 nm (6). The DSC curve of grafted compound 6

Chiral gels derived from secondary ammonium salts of (1R,3S)-(+)-camphoric acid

• Tapas Kumar Adalder,
• N. N. Adarsh,
• Ravish Sankolli and
• Parthasarathi Dastidar

Beilstein J. Org. Chem. 2010, 6, 848–858, doi:10.3762/bjoc.6.100

• table top rheology, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), single- and powder X-ray diffraction (SXRD and PXRD, respectively). Single crystal structures of two gelators and one nongelator, i.e., DBUAMC 3, DBAMC 6, and DCHADC 1, respectively were determined and

• Figure 1. To ascertain the thermoreversibility of the gel network, DSC was recorded on a selected gel sample derived from a ~4.0 wt % 1,2-dichlorobenzene solution of DBAMC 6 (Figure 2). It is clear from the DSC data that the gelation was indeed thermoreversible. However, both the sol-gel and gel-sol

• out with a JEOL, JMS-6700F, Field Emission Scanning Electro Microscope. Differential Scanning Calorimetry (DSC) was recorded with a Perkin-Elmer, Diamond DSC. Powder X-ray patterns were recorded on a Bruker AXS D8 Advance Powder (Cu Kα1 radiation, λ = 1.5406 Å) diffractometer. General Synthetic