The interaction between building blocks in the polymer hybrids plays an important role in their performance and functions. Herein, a novel multifunctional polymer hybrid with tunable charge transfer (CT) interaction between π-electron-poor naphthalenediimide (NDI) containing polyimide (PI) and π-electron-rich anthracene (AN) ended polyhedral oligomer silsesquioxane (POSS-AN) is reported (name the polymer hybrid “PI@POSS-AN”), in which the presence of CT interaction between NDI and AN and its controllable feature are confirmed by UV−vis and fluorescence spectra. A new absorption band at 500 nm in the visible region appears and the emission maxima of the CT complexes are distinctly red-shifted to 645 nm, while the fluorescence of NDI (493 nm) and AN (481 nm) are significantly quenched in the polymer hybrids. The resulting hybrid films are transparent and homogeneous, exhibit the enhanced thermal and mechanical performance with the increasing content of POSS-AN. Thanks to the reversible photodimerization of AN, CT interaction between NDI and AN can be on-off controlled in situ by UV light and heating, and rewritable fluorescence micro-patterns with red and green emission can be obtained. In addition, the cross-linked polymer hybrids possess healability and reprocessing performance.

The functionalization of a hydrogel with target molecules is one of the key steps in its various applications. Here, a versatile approach is demonstrated to functionalize a micropatterned hydrogel, which is formed by “thiol-yne” photo-click reaction between the yne-ended hyperbranched poly(ether amine) (hPEA-yne) and thiol-containing polyhedral oligomeric silsesquioxane (PEG-POSS-SH). By controlling the molar ratio between hPEA-yne and PEG-POSS-SH, patterned hydrogels containing thiol or yne groups are obtained. A series of thiol-based click chemistry such as “thiol-epoxy”, “thiol-halogen”, “thiol-ene”, and “thiol-isocyanate” are used to functionalize the thiol-containing hydrogel (Gel-1), while the yne-containing hydrogel (Gel-2) is functionalized through a typical copper-catalysed alkyne-azide reaction (CuAAC). FTIR, UV-vis spectra and confocal laser scanning microscopy (CLSM) are used to trace these click reactions. Due to the selective adsorption to the hydrophilic dyes, the obtained patterned hydrogel of hPEA modified with fluorescence dye is further demonstrated in application for the recognition of guest molecules.

Oxygen inhibition remains a challenge in photo-curing technology despite the expenditure of considerable effort in developing a convenient, efficient, and low-cost prevention method. Here, a novel strategy to prevent oxygen inhibition is presented; it is based on the self-assembly of multifunctional nano-photo-initiators (F₂-POSS-(SH)₄-TX/EDB) at the interface of air and the liquid monomer. These nano-photo-initiators consist of a thiol-containing polyhedral oligomeric silsesquioxane (POSS) skeleton onto which fluorocarbon chains and thioxanthone and dimethylaminobenzoate (TX/EDB) photo-initiator moieties are grafted. Real-time Fourier-transform infrared spectroscopy (FT-IR) is used to investigate the photo-polymerization of various acrylate monomers that are initiated by F₂-POSS-(SH)₄-TX/EDB and its model analogues in air and in N₂. FT-IR results show that F₂-POSS-(SH)₄-TX/EDB decreases the effects of oxygen inhibition. X-ray photo-electron spectroscopy and atomic force microscopy reveal that the self-assembly of F₂-POSS-(SH)₄-TX/EDB at the air/(liquid monomer) interface forms a cross-linked top layer via thiol–ene polymerization; this layer acts as a physical barrier against the diffusion of oxygen from the surface into the bulk layer. A mismatch in the shrinkage between the top and bulk layers arise as a result of the different types of photo-cross-linking reactions. Subsequently, the surface develops a wrinkled pattern with a low surface energy. This strategy exhibits considerable potential for preventing oxygen inhibition, and the wrinkled pattern may prove very useful in photo-curing technology.

The host–guest interaction between polymer nanoparticles and guest molecules plays a key role in fields such as controlled drug delivery, separation, and nanosensors. To understand this host–guest interaction, a series of hybrid polymer nanoparticles (SiO_1.5-hPEA NPs) are designed and prepared based on hyperbranched poly(ether amine) (hPEA) with the different hydrophobicity and functional groups. Their adsorption behavior to twelve hydrophilic dyes in aqueous solution is studied. The core-crosslinked hybrid nanoparticles (SiO_1.5-hPEA NPs) are prepared by direct dispersion of hPEA containing trimethoxysilyl moieties (TMS-hPEA) in aqueous solution, which exhibit sharp multiresponse to temperature, pH, and ionic strength in aqueous solution. The effect of molecular structure of TMS-hPEA on the host–guest interaction between SiO_1.5-hPEA NPs and hydrophilic dyes is investigated in detail. The obtained SiO_1.5-hPEA NPs interact selectively with different hydrophilic dyes in aqueous solution. The distribution coefficient (K) for partitioning of dyes between SiO_1.5-hPEA NPs and water is proposed to define the strength of the host-guest interaction between the nanoparticles and dyes. K increases with the increasing hydrophobicity of the hPEA backbone regardless of their charge states of SiO_1.5-hPEA NPs and dyes. A methodology is demonstrated for the smart separation of a mixture of dyes in water using SiO_1.5-hPEA NPs.

A novel hybrid resist for UV nanoimprint lithography (UV-NIL) based on the thiol–ene photopolymerization is presented. Our system comprises mercaptopropyl polyhedral oligomeric silsesquioxane and benzyl methacrylate, with trimethylolpropane trimethacrylate as the crosslinker. The obtained hybrid resists possess a variety of characteristics desirable for UV-NIL, such as low viscosity (6.1–25 cP), low bulk-volumetric shrinkage (5.3%), high Young's modulus (0.9–5.2 GPa), high thermal stability, and excellent dry-etch resistance. Based on these performances, the optimized components are evaluated as UV-NIL resists. The result is a high-resolution pattern with feature sizes in the range of 100 nm to several microns. The double-layer resist approach is used for pattern transfer into silicon substrates. The excellent oxygen-etch resistance of the barrier material enables a final transfer pattern that is about three times higher than that of the original NIL mold.

A series of amphiphilic polymeric Michler's ketone (MK) photoinitiators (APMKs) were synthesized by incorporating PEO short chain, MK moiety, and coinitiator amine into the same polymeric chain. APMKs possess good amphiphilic ability and become water-soluble when the molar ratio of MK(pipaz)₂/PEO/piperazine is 2:3:1. UV–Vis measurement shows that APMKs possess the same characteristic absorption to MK derivatives. The photopolymerization of three monomers with different functionality and hydrophilicity, polyethylene glycol diacrylate (PEGDA), phenoxy ethyl acrylate (AMP-10G), and 2,2-bis[4-(acryloxypolyethoxy)phenyl]propane (A-BPE-10) initiated by APMKs was investigated by photodifferential scanning (photo-DSC). The results show that APMKs can photoinitiate the polymerization of hydrophilic and hydrophobic monomers efficiently. As for photopolymerization of water-soluble PEGDA, the final conversion is higher than 94%. Therefore, APMKs will be expected to find potential in many fields. Copyright © 2009 John Wiley & Sons, Ltd.

A series of novel star-like copolymers H20-poly(N-isopropylacrylamide)-random-poly(poly(ethylene glycol) methyl ether methacrylate) (H20-PNIPAm-r-PEGMA), which could respond to both temperature and ionic strength stimuli in aqueous solution were synthesized by atom transfer radical polymerization. Stimuli-response of these copolymers in aqueous solution was characterized by dynamic laser scattering (DLS), ¹H-NMR and turbidity. In aqueous solution, these star-like copolymers exhibited response to temperature and ionic strength with tunable low-critical solution temperature (LCST) from 32 to 100°C. The LCST values of copolymers increased with increasing PEGMA contents, while decreased with increasing ionic strength. An interesting phenomenon, which should be a unique character of star-like copolymer, was observed by the turbidity test of copolymer 1160. The addition of sodium chloride and increase of concentration can let copolymer 1160 behave normally, which was further confirmed by atomic force microscopy and DLS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

A series of well-defined amphiphilic comb poly (ether amine)s (acPEAs) were successfully synthesized through nucleophilic addition/ring-opening reaction of commercial available poly(propylene glycol) (PPO) diglycidyl ether and Jeffamine L100, followed by esterification of hydroxyl groups in backbone by alkyl carboxylic acid with different chain length. acPEAs are comprised of hydrophilic short PEO chains and hydrophobic alkyl chains as comb chains, which are grafted on PPO backbone alternately to form well-defined structure. With the very low critical micelle concentration (CMC) of around 3.0 × 10⁻³ g/L, the obtained acPEAs can self-assemble into stable nanomicelles, whose aggregation is responsive to temperature, pH, and ionic strength with tunable cloud point (CP). The CP of acPEAs' aqueous solution increases with the decrease of the length of graft alkyl chains, the decrease of pH value, and the decrease of ionic strength. A transition behavior in the responsive aggregation of micelles formed by acPEA8 and acPEA10 in aqueous solution, especially at low pH value (<7.0), was observed, which was also revealed by DLS results. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3468–3475, 2010

Multistimuli-responsive hyperbranched poly(ether amine)s (hPEAs) were successfully synthesized through nucleophilic addition/ring-opening reaction of commercial diglycidyl ether and amine via one-pot synthesis. In aqueous solution, these hPEAs exhibited very sharp response to temperature, pH, and ionic strength, with well-tunable cloud point (CP). Through changing the poly(ethylene oxide) (PEO) chain content of hPEAs, pH, and ionic strength, the CP could be adjustable from 35 to 100 °C, and increased with the increasing of PEO content, the decreasing of pH and ionic strength. The CP of hPEAs aqueous solution presents a linear relationship to the PEO content in pH range from 6.6 to 8.0. Dynamic light scattering (DLS) investigation indicated that these hPEAs dispersed in aqueous solution to form the stable nanomicelles, whose aggregation can be controlled by temperature, pH, and ionic strength. Moreover, the obtained hPEAs contain reactive amino groups in periphery and hydroxyl groups inside, which can be further functionalized. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4252–4261, 2010

We reported that multiresponsive amphiphilic graft poly(ether amine)s (agPEAs) comprised of hydrophilic poly(ethylene oxide) (PEO) and hydrophobic octadecyl alkyl chain as side-chain were prepared through one-pot synthesis. In aqueous solution, these obtained agPEAs can self-assemble into stable nanomicelles, whose aggregation can be controlled by temperature, pH, and ionic strength with tunable cloud point (CP). In the presence of these obtained agPEAs, hydrophobic dye Nile red can be dispersed into aqueous solution and hydrophilic dye methyl orange can be dispersed into nonpolar toluene. The agPEAs are expected to be potential in application such as encapsulation and controlled release of drugs, due to their simple synthesis, amphiphilicity, and multistimuli response. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 327–335, 2010

A novel autophotosensitive polyimide (APSPI) was synthesized through introducing benzophenone (BP) moiety into the backbone chain and acrylate group into side chain of PI. The BP moiety can generate active radicals, which can initiate acrylate group to form crosslinked network. The study of photosensitive properties revealed its good photolithographic properties, with a resolution about 12 μm and a sensitivity of 330 mJ/cm². © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Multistimuli responsive grafted poly(ether tert-amine) (gPEAs), which were comprised of poly(propylene oxide) (PPO) in backbone and poly(ethylene oxide) (PEO) as grafted chain, were successfully synthesized through nucleophilic addition/ring-opening reaction of commercial poly(propylene glycol) diglycidyl ether and Jeffamine L100. These gPEAs exhibit very sharp response to temperature, pH and ionic strength with tunable cloud point (CP). The CP of gPEA aqueous solution increases with increasing the PEO content or decreasing pH value, varying from 27 to 77 °C. Compared with linear PEA101, gPEA110 of completely grafted structure in aqueous solution exhibits sharper response to temperature with ΔT around 1 °C. The results obtained from TEM and dynamic light scattering reveal that gPEAs are dispersed as uniform sized nano-micelles in aqueous at room temperature, which can further aggregate into mesoglobules of complex structure at high temperature (>CP). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6353–6361, 2009

A novel multiresponsive poly(ether tert-amine) (PEA) was synthesized by nucleophilic addition/ring-opening reaction of commercial poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), and di-epoxy and di-amine monomer. The process of synthesis was very simple and green in ethanol as reactive media. These PEAs exhibit sharp response to temperature, pH, and ionic strength, with adjustable and sharp phase transitions in the range of 27–100 °C. The lower critical solution temperature (LCST) of PEA's aqueous solution presents a linear relationship to the PEO content (y = 35.7 + x), indicating well-tunable LCST. The concentration of PEA has no obvious effect on LCST. Therefore, PEA will be potential in applications of drug delivery, separation, and biotechnology. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1292–1297, 2009