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The construction of a deep learning model and visualization of judgment regions were conducted for X-ray diffraction and scattering images of aliphatic polyesters. Due to recent progress in measurement methods, a large amount of image data can be obtained in a short time; therefore, machine learning methods are useful to determine the important regions for a given objective. Although techniques to visualize the judgment regions using deep learning have recently been developed, there have been few reports discussing whether such models can determine the important regions of X-ray diffraction and scattering images of polymeric materials. Herein, we demonstrate classification models based on convolutional neural networks (CNNs) for wide-angle X-ray diffraction and small-angle X-ray scattering images of aliphatic polyesters to predict the types of polymers and several crystallization temperatures. Furthermore, the judgment regions of the X-ray images used by the CNNs were visualized using the Grad-CAM, LIME, and SHAP methods. The main regions were diffraction and scattering peaks recognized by experts. Other areas, such as the beam centers were recognized when the intensity of the images was randomly changed. This result may contribute to developing important features in deep learning models, such as the recognition of structure–property relationships. The construction of a deep learning model and visualization of judgment regions were conducted for wide-angle X-ray diffraction and small-angle X-ray scattering images of aliphatic polyesters. The classification models based on convolutional neural networks (CNNs) for the X-ray images to predict the types of polymers and several crystallization temperatures were successively constructed. The judgment regions of the X-ray images used by the CNNs were visualized using the Grad-CAM, LIME, and SHAP methods. This result may contribute to developing important features in deep learning models, such as the recognition of structure–property relationships.

The mechanical stretching behavior of the poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS) triblock copolymer (87 wt% polyethylene-co-butylene (PEB), 13 wt% polystyrene (PS)) was investigated under three different stretching modes and through in situ small-angle X-ray scattering (SAXS) analysis. The strain energy density function was investigated based on the stress and stretching ratio (λ) relationship under uniaxial, planar extension, and equi-biaxial stretching modes. As a result, the cross-effect of strain represented by the second invariants of the deformation tensor (I2) was identified, and only the Ogden model found to fit the data. In the cyclic stretching tests, SEBS exhibited smaller hysteresis during cyclic equi-biaxial stretching compared to uniaxial stretching. In other words, the Mullins effect was found to be more obvious for uniaxial stretching than equi-biaxial stretching. The λ and the stretching ratio obtained from the crystal planes by SAXS (λSAXS) were compared to investigate the relationship between the change in the microdomain structure and the macroscopic mechanical properties. Thus, affine deformation was found to occur in the smaller λ region for both uniaxial and equi-biaxial stretching and deviation from affine deformation occurred for uniaxial stretching in the larger λ region. This is because the entangled loops of PEB chains serve as cross-linking points when the films are stretched under equi-biaxial stretching. The mechanical stretching behavior of poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS) was investigated under three different stretching modes and through in situ SAXS analysis. SEBS exhibited smaller hysteresis during cyclic equi-biaxial stretching than that of uniaxial stretching. SAXS measurement revealed that affine deformation occurred in the smaller stretching ratio (λ) region for both uniaxial and equi-biaxial stretching modes and deviation from affine deformation occurred for uniaxial stretching mode at the larger λ region. This is because entangled loops of poly(ethylene-co-butylene) chains serves as cross-linking points when films are stretched under equi-biaxial stretching mode.

The specific deformation behavior of crystalline polymer films, namely unoriented crystallized isotactic polypropylene (it PP) films, was investigated under a multiaxial stress field.

The strength of silica-based mechanochromic nanocomposites was improved by a novel nanocomposite synthesized by grafting poly(butyl acrylate) (PBA)-b-poly(methyl methacrylate) (PMMA) from silica na...

Polylactide (PLA) exhibits various types of crystal modifications depending on the preparation conditions, including the components. To solve the open question, a reliable calculation method for crystallinity, crystal forms, and composition in neat PLA and PLA composites was developed on the basis of temperature-dependent synchrotron wide-angle X-ray diffraction results. The relative composition of amorphous, α-form, and α’-form phases of PLA and its composites filled with halloysite nanotubes during heating was successfully obtained. It was found that only 47–56% of α’-form crystals transform into α-form crystals during a 2 °C/min heating process for PLA with a molecular weight of 54,300 g/mol. The loading of halloysite nanotubes decreases the cold crystallization and starting transition (α’ crystals transform into α-form crystals) temperatures of PLA. The crystallinity and the main diffraction peak intensity as a function of temperature were also analyzed. These results suggest that the α’-to-α form transition is a solid-solid phase transition. Polylactide (PLA) exhibits various types of crystal modifications depending on the preparation conditions, including the components. To solve the open question, a reliable calculation method for crystallinity, crystal forms and composition in neat PLA and PLA composites was developed on the basis of temperature-dependent synchrotron wide-angle X-ray diffraction results. The relative composition of amorphous, α-form, and α’-form phases of PLA and its composites filled with halloysite nanotubes during heating was successfully obtained.

Molecular mechanisms underlying the cononsolvency, a re-entrant coil-to-globule-to-coil conformational transition of polymer chains in mixtures of two good solvents, of poly[2-(methacryloyloxy)ethyl phosphorylcholine] (PMPC) in ethanol-water binary mixtures were complementarily investigated. This was accomplished by following a statistical mechanical model for competitive hydrogen bonding combined with the cooperative solvation concept as well as neutron reflectivity (NR) experiments employing contrast variation in the cononsolvents. The experimental re-entrant aggregation of the PMPC chains in ethanol-water mixed solvents, obtained on the basis of turbidity was accurately reproduced by theoretical calculations. The calculation proved the relatively strong cooperativity of ethanol and the preferential interaction of water, while the total coverage of solvents was the lowest at an ethanol volume fraction (fethanol) of 0.90. At this level, the cononsolvency was the most significant, and the collapsed PMPC chains were solvated with more water than the bulk mixed solvent. The ethanol-water cononsolvency for the PMPC brushes on a planar silicon wafer was investigated by NR experiments, and the solvent composition involved in the collapsed PMPC brush was addressed according to the contrast variation study with mixed solvents of water, deuterium oxide, ethanol-d5, and ethanol-d6. The collapsed PMPC brushes at fethanol = 0.90 contained more water than the bulk solvent. The preferential distribution of water in the collapsed PMPC brush was consistent with the simulation results. Therefore, the molecular mechanism for the cononsolvency of PMPC in ethanol-water mixed solvents based on competitive hydrogen bonding coupled with cooperative solvation was experimentally rationalized.

Liquid crystal elastomers can vary their shape freely with no extra mechanical energy like liquids when deformed in the plane., When isotropic solids are unequally stretched in two orthogonal directions, the true stress (force per actual cross-sectional area) in the larger strain direction is typically higher than that in the smaller one. We show that thiol-acrylate liquid crystal elastomers with polydomain texture exhibit an unusual tendency: The true stresses in the two directions are always identical and governed only by the area change in the loading plane, independently of the combination of imposed strains in the two directions. This feature proves a previously unidentified state of matter that can vary its shape freely with no extra mechanical energy like liquids when deformed in the plane. The theory and simulation that explain the unique behavior are also provided. The in-plane liquid-like behavior opens doors for manifold applications, including wrinkle-free membranes and adaptable materials.

The deformation behavior of polythiourethane (PTU) elastomers was investigated using in situ small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD), and X-ray absorption fine stru...

Nanocomposites composed of monodisperse silica nanoparticles (SiNPs) modified with an elastic comb-shaped block copolymer brush were produced for the first time. Comb-shaped polymer brushes consisting of glassy poly(methyl methacrylate) branches and a rubbery poly(butyl acrylate) backbone were grafted from 100 nm diameter SiNPs by surface-initiated atom transfer radical polymerization. The comb-shaped polymer brush-grafted SiNPs produced self-standing films with a face-centered cubic ordered lattice structure via solvent-casting. The composite films showed rubber elasticity because of the interparticle rubbery polymer brush boundary phase. The ordered lattice exhibited significant alignment and distortion in response to the macroscopic film strain, and then reproduced the initial ordered lattice after unloading.

The local mechanical properties of crystalline polymer were evaluated using synchrotron radiation X-ray diffraction with 10 μm lateral resolution. A nonoriented isotactic polypropylene (iPP) film with isolated spherulites in a crystallized matrix was used as a model sample. In situ wide-angle X-ray diffraction (WAXD) measurement was performed on the iPP film using a microbeam synchrotron radiation X-ray under sinusoidal strain. The lattice spacing of the crystal planes increased and decreased in response to the applied sinusoidal strain. Local dynamic viscoelastic functions (dynamic storage and loss moduli (

Polythiourethane (PTU) and polyurethane (PU) elastomers were prepared from poly(oxytetramethylene) glycol, 1,4-bis(isocyanatomethyl) cyclohexane and a dithiol or diol chain extender with two methylene numbers (tetramethylene (C4) and pentamethylene (C5)). The effect of dithiol and diol and the methylene length of the chain extenders on the microphase-separated structure and mechanical properties of PTU and PU were evaluated. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction measurements revealed that the degree of ordering of hard segment chains in PTUs is lower than that for PU elastomers. However, it was revealed from the DSC, small-angle X-ray scattering and temperature dependent dynamic viscoelasticity measurements that the degree of microphase separation in the PTUs became stronger than that for the PUs. As a result, the mechanical property of PTUs is comparable with PUs. Furthermore, the glass transition temperature for the soft segment of PTU became lower than that for PU. PTU and PU exhibited a larger degree of microphase separation and mechanical property when the chain extender was composed of a tetramethylene (C4) chain compared to a pentamethylene (C5) chain. Polythiourethane (PTU) elastomers, which are obtained by the reaction between polyol, diisocyanate, and dithiol, are expected to have some properties that polyurethanes (PUs) do not have. Herein, the microphase-separated structure and mechanical properties of the 1,4-bis(isocyanatomethyl) cyclohexane-based PTUs were investigated. It was revealed from the differential scanning calorimetry, small-angle X-ray scattering and dynamic viscoelasticity measurements that the PTUs possess a stronger degree of microphase separation and lower glass transition temperature of soft segment compared to that of PUs.

Summary The complicated structure-property relationships of materials have recently been described using a methodology of data science that is recognized as the fourth paradigm in materials science. In network polymers or elastomers, the manner of connection of the polymer chains among the crosslinking points has a significant effect on the material properties. In this study, we quantitatively evaluate the structural heterogeneity of elastomers at the mesoscopic scale based on complex network, one of the methods used in data science, to describe the elastic properties. It was determined that a unified parameter with topological and spatial information universally describes some parameters related to the stresses. This approach enables us to uncover the role of individual crosslinking points for the stresses, even in complicated structures. Based on the data science, we anticipate that the structure-property relationships of heterogeneous materials can be interpretatively represented using this type of “white box” approach., Graphical Abstract, Highlights • Developed network indicator with both connectivity and spatial distance between nodes • Network indicator used as a mesoscopic descriptor of network polymers or elastomers • Mesoscopic descriptors universally represented certain parameters related to stress • Incorporating spatial distance into closeness centrality is useful for other materials, The Bigger Picture Complex network science has contributed to extracting essential parameters from network structure and has been applied in social, geographical, computer, and biological sciences. On the other hand, in materials science, some materials possess a network structure that determines their properties. Because both connectivity and spatial distance are significant factors in materials, utilizing a combined descriptor to explain their properties could be important. In this study, we demonstrate that the descriptor with both connectivity and spatial distance prior to elongations universally represented some parameters related to mechanical properties during elongation, which enabled us to interpret the role of each node. Recently, there have been significant attempts to develop new materials by methods in data science such as materials informatics. Thus, our approaches could contribute in the future to the development of materials with network structures in an interpretable manner., Network polymers comprise materials encountered in our daily life, such as foam rubbers, adhesions, and rubber tires. The mechanical properties of network polymers or elastomers depend on the network structure; however, the heterogeneity of the connectivity is difficult to evaluate quantitatively. A mesoscopic descriptor of network polymers was developed to describe the structure-mechanical property relationships based on closeness centrality, a complex network indicator. The mesoscopic descriptor with both topological and spatial information universally represented parameters that determine the mechanical properties.

Hard segments of polyurethanes (PUs) are generally formed from diisocyanate and diol. Diol can be replaced with triol and thiol. These chemical structures of hard segments strongly affect not only a microphase separated structure but mechanical properties of resultant PUs. In this review, we focus on the relationship between chemical structure like symmetry and bulkiness of diisocyanate and mechanical properties of PU. Then, influence of hard segment content, incorporation of 1,1,1-trimethylol propane with trifunctional groups, and alkyldithiol was reviewed mainly on trans-1,4-bis(isocyanatomethyl) cyclohexane-poly(oxytetramethylene) glycol-based PU.

The crystalline structures of isotactic polypropylene (iPP) thin films were investigated using grazing incident wide-angle X-ray diffraction (GIWAXD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The out-of-plane (110) reflection split with 99° inclination in the GIWAXD pattern. The film surface was covered with flat-on mother lamellae with orthogonal daughter lamellae. The cross-sectional TEM image and the fast Fourier transform-processed image showed vertically aligned daughter lamellae and cross-hatched lateral mother lamellae. Flat-on lamellae may be preferentially produced at the substrate interface, after which the mother lamellae may yield daughter lamellae from the ac plane to give vertically aligned lamellae. The daughter lamellae yield in-plane lamellae with flat-on alignment from the ac plane, resulting in the global growth of a cross-hatched lamellar structure. Grazing incidence wide-angle X-ray diffraction study of lamellar orientation in isotactic polypropylene thin films. Crystalline structure of isotactic polypropylene (iPP) thin films was investigated by means of grazing incident wide-angle X-ray diffraction, atomic force microscopy, and transmission electron microscopy. Flat-on mother lamellae with orthogonal daughter lamellae form in the thin film. We propose a lamellar growth model for iPP thin films in which the crystallization progresses flat-on mother lamellae at the substrate interface to out-of-plane growth of daughter lamellae from the mother lamellae.

It is desirable to establish a method for evaluating mechanical properties, such as modulus and strength, of micrometer and sub-micrometer thick polymer films. Bulge tests, where bulge deformation is imposed on films by the pressure of an inert gas, are suitable for satisfying this demand. However, very few studies on polymer films exist in the literature. In this study, bulge testing equipment for in situ synchrotron radiation wide-angle X-ray diffraction (WAXD) measurements is designed and used to study the relationship between the molecular aggregation structure and the mechanical properties of a crystalline nylon 12 (Ny12) film during bulge testing. Isothermally crystallized and quenched Ny12 films exhibited stress-strain curves similar to those obtained by conventional uniaxial elongation. In situ WAXD measurements during bulge testing revealed that the lattice extension of the crystallites is clearly dependent on crystallinity. Concretely, crystallites in the isothermally crystallized film show higher elastic properties than those in the quenched one. The results of the molecular aggregation structure, including the crystal structure and the amorphous chain surrounding the crystallites, of the films during bulge deformation firstly obtained in this study must be useful for designing toughened polymer films.

Transformable double hydrophilic block copolymer assemblies are valid as a biocompatible smart macromolecular system. The molecular mechanisms in the spontaneous assembly of double zwitterionic diblock copolymers composed of a poly- (carboxybetaine methacrylate) (PCB2) and a poly(sulfobetaine methacrylate) (PSB4) chains (PCB2-b-PSB4) were investigated by the modulation of the aggregates in response to nondetergent zwitterions. The PCB2-b-PSB4 diblock copolymers with a high degree of polymerization PSB4 block produced aggregates in saltfree water through “zwitterion-specific" interactions. The PCB2-bPSB4 aggregates were dissociated by the addition of nondetergent sulfobetaine (SB4) and carboxybetaine (CB2) molecules, while the aggregates showed different aggregation modulation processes for SB4 and CB2. Zwitterions with different charged groups from SB4 and CB2, glycine and taurine, hardly disrupted the PCB2-b-PSB4 aggregates. The PCB2-b-PSB4 aggregate modulation efficiency of SBs associated with the intercharge hydrocarbon spacer length (CSL) rather than the symmetry with the SB in the PSB chain. These zwitterion-specific modulation behaviors were rationalized based on the nature of zwitterions including partial charge density, dipole moment, and hydrophobic interactions depending on the charged groups and CSL.

Biocompatible and blood-compatible surface modification is urgently needed for stainless steel (SUS)-based human implant devices to avoid inflammation and biofouling. To this end, the use of polymeric surface modifiers, whose surface properties are specifically tailored, is a promising approach since this approach minimizes the impact on device's mechanical properties. However, adhesion between the device and surface modifier is relatively weak, since van der Waals forces are employed, leading to low device durability. To address this issue, this work functionalized poly(ɛ-caprolactone)-b-[poly(α-chloride-ɛ-caprolactone)-b-poly(2-methacryloyloxyethyl phosphorylcholine)]2 (PCL-b-(PCL-Cl-b-PMPC)2) with catechol groups via a nucleophilic substitution, whereby the catechol functionalization was optimized. The resultant surface modifier showed strong adhesion toward SUS surfaces, forming a smooth and uniform hydrophilic polymeric film that reduced SUS fouling (i.e., protein). Notably, no significant changes of adhesion between the SUS and thin films (thin film) were observed after immersion for 45 days in a pH 7.4 phosphate buffer solution. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 38–49

The effect of molecular mobility of a pre-crystallized phase on the isothermal crystallization in the microphase-separated lamellar morphology of a strongly segregated crystalline-crystalline block copolymer, poly(ethylene glycol)- block -poly(perfluorooctylethyl acrylate) (PEG- b -PFA-C 8 ), was investigated. The diblock copolymer produced a microphase-separated lamellar morphology in the melt state, and the precedent crystallization of PFA-C 8 blocks provided the lamellar confinement field. The counter PEG block crystallized within the lamellar confinement field. The molecular mobility of the pre-crystallized PFA-C 8 phase was modulated by the thermal history. The structural evolution was monitored by a complementary combination of in situ time-resolved simultaneous small-angle X-ray scattering/wide-angle X-ray diffraction measurements and thermal analyses. The degree of crystallinity and the melting temperature of the PEG crystals were associated with the molecular mobility of the pre-crystallized PFA-C 8 phase. The highly packed PFA-C 8 phase (higher-ordered phase) constrained the PEG crystallization, whereas the loosely packed PFA-C 8 phase (lower-ordered phase) caused a weak restriction in the PEG crystallization to give relatively ordered PEG crystals. Subsequent crystallization in a confinement field of crystalline-crystalline block copolymers was controlled by adjusting the molecular mobility of the pre-crystallized phase.

Polyurethane elastomers (PUEs) containing trans-1,4-bis(isocyanatomethyl)cyclohexane (1,4-H6XDI) have been synthesized by polymerizing 1,4-H6XDI with poly(oxytetramethylene) glycol and 1,4-butanediol. The molecular aggregation state and mechanical properties of these PUEs have been compared with those exhibited by PUE analogues made of MDI and diols. The hard segment chains in the 1,4-H6XDI-based PUEs are found to readily crystallize and form strong hydrogen bonds due to a high symmetry of 1,4-H6XDI molecule. Consequently, the 1,4-H6XDI-based PUEs exhibit well-organized hard segment domains. This leads to their generally superior mechanical properties as compared to those of the well-known MDI-based PUEs. 1,4-H6XDI’s lack of aromatic moieties is expected to greatly enhance color stability of resulting PUEs. All the above features suggest 1,4-H6XDI could replace MDI in a range of applications.

Soft denture liners and tissue conditioners are widely used for the denture patients to cushion masticatory force and condition abused tissues, respectively. This study assessed methods for the evaluation of the viscoelasticity and glass transition temperature (Tg) of the silicone permanent soft liner, acrylic permanent soft liner, and tissue conditioner. Three rheological parameters of storage modulus (E′), loss modulus (E′′), and loss tangent ($$\tan \delta$$), Tg, and hardness were determined using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and the Shore A0 hardness test. Five specimens were measured for each material. The time–temperature superposition principle was applied to produce master curves of E′, E′′, and $$\tan \delta$$ for the tested materials at a reference temperature of 37 °C. The acrylic permanent soft liner and tissue conditioner exhibited viscoelastic behavior and sensitivity to frequency, especially at lower frequencies. The silicone permanent soft liner showed elastic behavior and was frequency-independent. Tg for the acrylic permanent soft liner was higher than that for the tissue conditioner, which in turn was higher than that for the silicone permanent soft liner for both DMA and DSC. In DMA, a higher frequency led to higher Tg values. A positive linear relationship was found between Shore A0 hardness and E′ values, but not E′′ and $$\tan \delta$$ values. Shore hardness reflects elasticity, but not viscosity. The results of the present study can be used to improve methods for evaluating the viscoelasticity and Tg of soft denture liners and tissue conditioners.

We have prepared the amidinium-carboxylate salt bridge-based supramolecular network polymers from a carboxy-terminated telechelic poly(n-butyl acrylate) and a linear polyamidine having N,N′-di-substituted acetamidine group in the main chain. FTIR measurements indicated that the salt bridge was attributed to the three-dimensional network formation. Virtually, no fluidity was observed for the blend containing equimolar amounts of the carboxyl group and the amidine group, which showed a high G′ value of about 1 MPa at −5 °C. For comparison, the supramolecular network polymers crosslinked by ammonium-carboxylate salt were prepared using a linear polyethyleneimine instead of the polyamidine. The blend with equimolar amounts of the carboxyl group and the secondary amino group showed liquid-like fluidity with a G′ value of about 0.01 MPa at −5 °C, which was attributed to the fact that a certain amount of the carboxyl group remained as its free form, as evidenced by FTIR analysis. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2148–2155

A solvent free oxidative coupling reaction of 3-hexylthiophene (3HT) within a nanocavity is reported. It is found that 3HT can be encapsulated in nanocavities larger than 1 nm, which corresponds to the size of the molecule. In this case, the side reaction at the 4-position in 3HT is regulated.

Crystallization-induced structure fluctuations in the layer thickness direction and disordering of pre-crystallized structure in crystallized microdomain structure that consist of a strongly segregated crystalline-crystalline diblock copolymer, poly(ethylene glycol)- block -poly(perfluorooctyl ethyl acrylate) (PEG- b -PFA-C 8 ), were investigated. The structure formation process during isothermal crystallization was monitored by in-situ time-resolved simultaneous SAXS/WAXD measurements and thermal analysis. At early stage of isothermal crystallization, three dimensional growth of the PEG lamellar crystals within lamellar microphase-separated morphology induced the volume shrinkage of PEG phase, resulting in the reduction of PEG layer thickness, increase of PFA-C 8 layer thickness and disordering of pre-crystallized PFA-C 8 crystals. At late stage of isothermal crystallization, one dimensional growth, thickening of PEG lamellar crystals induced the increase of PEG layer thickness and reduction of PFA-C 8 layer thickness. The structure fluctuation in the crystallized microdomain structure depends on the crystal growth dimension.

Natural rubber (NR) films from various mixing ratios of large- (LRP) and small rubber particles (SRP) were prepared through latex and solution casting methods. Film-forming behaviours of the resulting films were investigated by monitoring their surface characteristics using atomic force microscopy (AFM). When the SRP portion was higher, the surface of the latex-cast films was found to be smoother as smaller particles protruded out of the surface less than larger ones did. AFM phase micrographs revealed a hexagonal shape of packed rubber particles (RPs) of the LRP film, while the RPs in the other samples were sphere-like. After aging under ambient conditions, the packed RPs were flattened while retaining their RP boundaries, creating a supporting framework within the rubber matrix. On the contrary, when the rubber film was cast from a toluene solution, the characteristic of RP boundaries disappeared and became aggregates of the membrane components on the film surface. The latex-cast films performed much better in mechanical strength than the solution-cast films did due to the destruction of the supporting framework arisen from the non-rubber components at the RP boundaries of the solution-cast film. An inhomogeneous density distribution produced by the non-rubber aggregates in the latex-cast films was observed in small angle X-ray scattering measurements.

The synergistic interactions between the α-amine and the carboxylic acid in an amino acid have recently been studied as bio-based zwitterions. Here, we report a new amphiphilic polymer containing glutamic acid grafted to the end of a dodecyl polymer side chain, which contains the α-amine and the γ-carboxylic acid of the glutamic acid moiety. The polymer self-assembled into a multilayered structure in the thin film, and the glutamic acid moieties in the polymer side chains were exposed to the polymer film/water interface. Annealing the sample enhanced the formation of a well-oriented lamellar structure in the films. Due to the presence of the glutamic acid moieties at the interface, the surface charge was controllable by pH in buffer solutions, resulting in zwitterionic character at neutral pH. It has been widely accepted that zwitterionic surfaces can exhibit non-fouling for proteins. Interestingly enough, the polymer film showed charge-selective protein adsorption since the synergistic interaction between the α-amine and the γ-carboxylic acid was weaker than conventional amino acid-based zwitterionic systems. This is due to the separated state of the functional groups by a three carbon spacer.

Dispersion of C60/silica nano-composite, prepared by inclusion of C60 into grafted polymer chains on silica, in organic solvent and poly(methyl methacrylate) (PMMA) matrix was investigated. The polymer-grafted SiO2 particles were prepared by grafting of poly(methyl methacrylate-co-2-naphthyl methacrylate) onto colloidal silica of 9.1 nm in diameter. Inclusion of C60 into the grafted polymer chains was significantly dependent on molecular weight of the polymer and independent on amounts of grafted polymer. The C60/SiO2-PMMA hybrid film, composed of 0.21% C60 and 10% SiO2, showed high transparency in visible light region.