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In this study, we report for the first time the thin film morphology and property characteristics of a series of adamantane-containing polymers, which were investigated by using synchrotron grazing incidence X-ray scattering, X-ray reflectivity and spectroscopic ellipsometry. The chemically incorporated monomeric and dimeric adamantane units could disturb regular chain packing, ultimately producing amorphous polymers. They further tend to randomize chain orientations even in nanoscale thin films; surprisingly, random chain orientations could be achieved even for thermally-annealed thin films, which are quite different from the in-plane orientations of conventional polymer films being enhanced by thermal annealing. As a result, isotropic optical refractive indices and dielectric constants could be demonstrated even in nanoscale thin films, which are highly demanded for the production of advanced microelectronic devices. Moreover, the adamantane units incorporated into the backbone and as primary side groups could significantly reduce the dielectric constant, refractive index, critical angle, electron density and mass density of polymer. Overall, the positive impacts of incorporated adamantane units are huge on the polymer morphology and properties. All adamantane-containing polymers of this study are suitable materials for advanced microelectronics, which can replace current workhorse dielectrics, such as silicon oxide, silicon nitride, and polyimides, being used in microelectronic devices.

Novel one-handed helical copoly(phenylacetylene)s bearing a small amount of 3-(triethoxysilyl)propyl residues (CPAs 1–4) were synthesized, and efficiently chemically immobilized onto silica gel by the intermolecular polycondensation of the triethoxysilyl groups. Their chiral recognition abilities were evaluated as immobilized-type chiral stationary phases (CSPs) for high performance liquid chromatography (HPLC). These immobilized-type CSPs showed different chiral recognition abilities from the corresponding coated-type CSPs, which may be ascribed to the conformational change in the copoly(phenylacetylene)s during the immobilization process according to the diffuse reflectance circular dichroism (DRCD) measurement of the copolymer. In addition, the immobilized-type CSPs showed a universal solvent tolerability, for instance, CHCl 3 -containing eluents that cannot be used with the corresponding coated-type CSPs could now be used for the immobilized-type CSPs so that the chiral recognition of i -CSP-2 for the racemic 1-(9-anthyl)-2,2,2-trifluoroethanol (5) was improved with separation factors comparable or higher than those obtained on the popular polysaccharide-based CSPs. The intermolecular polycondensation of the triethoxysilyl groups of the copoly(phenylacetylene)s is a valuable immobilization method for poly(phenylacetylene)-based CSPs.

The guest release and solution behavior during shell disruption of a polymeric nanocapsule are described. Hyperbranched polyethylenimine (PEI, Mn = 10 000) is chemically functionalized with multiple DAD hydrogen-bonding motifs (D and A: hydrogen-bonding donor and acceptor), leading to PEI232–(DAD)x (3) (x = 93 (3a), x = 46 (3b), x = 23 (3c), x = 12 (3d)). Meanwhile, polyethylene oxide (Mn = 2 200) is end-capped with thymine moieties (PEO–ADA) (4). Mixing of the hydrogen-bonding complementary 3 and 4 (DAD/ADA = 1) leads to a physical micelle (3·4) in apolar media, and the resulting micelle can completely and irreversibly transfer the ionic and water-soluble Congo red (CR) into chloroform phase by encapsulation. Experiment proves that the micelle can exist as a pseudo-unimolecular micelle (p-UIM, meaning one PEI in one micelle) or as aggregate, depending on the shell density. As a result, 3b·4 generally exists as a p-UIM while 3d·4 can exist as p-UIM only in a very narrow range of concentrations. The critical aggregation concentration (CAC) is also dependent on the core structure of the micelle, thus when the residual amines in the core of 3b are transformed into amide, the resulting 5b·4 shows a very low CAC. Small chemicals bearing DAD hydrogen-bonding motif can compete to bind with the PEO–ADA shell and destruct the p-UIM, leading to aggregation and precipitation of the p-UIM along with the CRs. Experiment proves that the CR has strong acid–base interaction with the PEI core of the p-UIM, but when the basicity of the PEI core is reduced by amidation, partial CRs can be released into the water phase.

Hyperbranched polythreitol (1) with different molecular weights (Mw,SLS: 1.18 × 104 and 4.79 × 104) was reacted with trityl chloride in DMF to afford a novel amphiphilic polymer (2) consisting of 1 as the hydrophilic core and the trityl groups as the hydrophobic shell. Compound 2 was tested for its ability to act as a unimolecular nanocapsule toward the water-soluble dye, rose bengal (RB). Their encapsulation and release properties were also evaluated by comparison with the degree of substitution (DS) of the trityl groups, i.e., the hydrophobic shell density. The polymers were found to have very good unimolecular nanocapsule characteristics even at extremely low concentrations. The average number of RBs per polymer molecule depended on the hydrophilic core size and the hydrophobic shell density. The increasing DS value led to a decrease in the encapsulated amount due to the decrease in the hydrophilic core space, while the low DS value (less than ca. 20 mol%) led to a destabilization as a unimolecular nanocapsule and a lower encapsulation ability. In particular, 2 with ca. 23% DS value showed an efficient encapsulation. Based on a release test of the RB-loaded unimolecular nanocapsules, the polymers showed a high RB-holding ability in water.

The synthesis of a novel unimolecular reverse micelle, the hyperbranched d -glucan carbamate ( 3 ), was accomplished through the carbamation reaction of the hyperbranched d -glucan ( 1 ) with the N -carbonyl l -leucine ethyl ester ( 2 ) in pyridine at 100 °C. Polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1 . The degree of carbamate substitution (DS) for 3 was controlled by the feed rate of 2 , and the DS values were in the range of 46.0–93.7%. Polymer 3 possessed the encapsulation ability for water-soluble molecules, such as rose bengal, thymol blue, and alizarin yellow in chloroform, and the encapsulation ability depended on the hydrophilicity of 3 and the molecular size of the dye. The rose bengal (RB) encapsulated polymer (RB/ 3 ) showed a slow release from the RB/ 3 system into water at neutral pH, while the release rate was significantly accelerated by the hydrolysis of the hydrophobic polymer shell under basic conditions.

4-Vinylbenzyl glucoside peracetate (1) was copolymerized with divinylbenzene (DVB) using 1-phenyl-1-(2′,2′,6′,6′-tetramethyl-1′-piperidinyloxy)ethane (2) as an initiator in m-xylene at 138 °C for 20 h ([DVB]/[2]=28; [DVB]=0.62 mol L−1). The copolymerizations were performed using the mole fraction of 1 in the total feed of 1 and DVB (F1: [1]/[1]+[DVB]) ranging from 0.11 to 0.38 that produced the polystyrene (PSt) microgel with acetyl glucose, 3, in 46–53% yields. Dynamic laser light scattering (DLS) measurements showed that 3 was stably suspended in toluene as particles with average diameters (d's) ranging from 12 to 22 nm. A static laser light scattering (SLS) measurement gave the average molar mass, Mw,SLS, of 3 that ranged from 9.69×104 to 6.96×105. The numbers of the 1, 2, and DVB units in 3 (N1, N2, and NDVB, respectively) were from 111 to 238, from 17 to 208, and from 350 to 4510, respectively. The deacetylation of 3 was achieved by treatment with sodium methoxide in dry 1,4-dioxane to produce the PSt microgel with glucose as the hydrophilic segment, 4. The solubilities of 4 in toluene, CHCl3, THF, 1,4-dioxane, pyridine, DMF, DMSO, and H2O, and the mixture of H2O and 1,4-dioxane were examined, indicating that a hydrophilic property had been effectively introduced into 4.

4-Vinylbenzyl glucoside peracetate 1 was polymerized with α,α′-bis(2′,2′,6′,6′-tetramethyl-1′-piperidinyloxy)-1,4-diethylbenzene 2 in chlorobenzene using (1 S )-(+)-10-camphorsulfonic acid anhydrous (CSA) as an accelerator ([ 1 ]=0.4 M,[ 1 ]/[ 2 ]/[CSA]=75/1/1.3) at 125 °C for 5 h. The polymerization afforded poly(4-vinylbenzyl glucoside peracetate) having TEMPO moieties on both sides of the chain ends, 3 , with a molecular weight ( M w,SLS ) of 8500, a polydispersity index ( M w / M n ) of 1.09, and an average degree of polymerization of the 1 unit ( x ) of 17. Styrene (St) was polymerized with 3 in chlorobenzene at 125 °C (St/chlorobenzene=1/2, w/w). The polymerization successfully afforded polystyrene–poly(4-vinyl glucoside peracetate)–polystyrene, 4 , when the polymerization time was below about 2 h. Polymer 4 with the M w,SLS of 12,500, 17,900, and 29,400, the compositions ( y – x – y ) of 20–17–20, 45–17–45, and 100–17–100, and the M w / M n of 1.12, 1.14 and 1.17 were modified by deacetylation using sodium methoxide in dry-THF into polystyrene–poly(4-vinyl glucoside peracetate)–polystyrene, 5 . The solubility of polymer 5 was examined using a good solvent for polystyrene such as toluene and for the saccharide such as H 2 O.

The chiral recognition property of poly [(1 → 6)-2,5- anhydro -3,4- di -O- methyl- d -glucitol ] ( 2b ) towards racemic RCH(CO 2 CH 3 )NH + 3 ·X − (3·HX) has been studied using a transport system involving an aqueous source and receiving phases separated by a chloroform phase containing 2b . For HPF 6 , HClO 4 and HCl salts of 3a (R = Ph), the amount of 3a transported into the receiving phase decreased in the order of PF − 6 > ClO − 4 > Cl − , but the optical purities changed only slightly from 9.3 to 10.9%. The transport rates for aromatic guests, 3a and 3b (R = CH 2 Ph, were faster than those for aliphatic ones, 3c (R = CH(CH 3 ) 2 ) and 3d (CH 2 CH(CH 3 ) 2 ), using PF − 6 as the counterion. The optical purity was 10.9% for 3a as a maximum value and decreased in the order of 3a > 3c > 3b and 3d . The formationof a complex between 2b and 3a ·HX was confirmed by 1 H and 13 C n.m.r. spectral measurements.