Electron-rich thiophene-flanked thiazoloisoindigo (Th-TzII) has been reported as a building block for ambipolar polymeric field-effect transistors however with preferable hole transport. Here, we report that by using an electron deficient thiazole as the flanked moiety, the corresponding thiazoloisoindigo (Tz-TzII) can still be synthesized, although in a more sinuous way. Theoretical calculation and experimental results demonstrate that Tz-TzII is more electron-deficient than Th-TzII, and the corresponding polymer P(TzII-Tz-T-Tz) exhibits high and balanced hole/electron mobility of 0.70/0.64 cm²·V⁻¹·s⁻¹.

Incautious discharge of organic dyes such as methyl orange (MO) has produced serious pollution to the environment, calling for the efficient techniques to remove them with retaining the green world. The photo-catalytic degradation of organic dyes is promising among the developed techniques. Thus, a strategy based on transpiration-prompted photocatalytic degradation of dye pollutant under sunlight is put forward. Aniline (ANI) is graft-polymerized onto poly(acrylamide-co-N-4-aminophenylacrylamide) (PAAm) cryogel embedded with gold nanoparticles (AuNPs, diameter: 4−10 nm). The obtained cryogels integrated with AuNPs and PANI inside PAAm matrix (AuNP@PAAm-g-PANI) have been structurally explored based on the chemical composition and the phase/porous morphology. SEM and TEM observation shows that PANI and AuNPs are uniformly distributed in PAAm matrix. Since the macro-porosity of cryogel, hydrophilicity of PAAm and photo-thermal activity of PANI, PAAm-g-PANI cryogels without AuNPs can have a photo-thermal evaporation rate of water at 1.63 kg·m⁻²·h⁻¹. As a comparison, AuNP@PAAm-g-PANI cryogels with AuNPs exhibit higher one at 2.20 kg·m⁻²·h⁻¹, suggesting the promotion of AuNPs to photo-thermal evaporation. Meanwhile, PANI appreciatively assists AuNPs to display higher catalytic ability for the oxidative degradation of MO. Therefore, the removal of MO from water is obviously prompted by the water transpiration under sunlight with AuNP@PAAm-g-PANI cryogels, whose rate constant can reach to 0.320 h⁻¹, being three folds of that for the sole absorption of MO. This transpiration-prompted photocatalytic degradation provides a fascinating route to eliminate organic pollutants and obtain pure water from wastewater simultaneously with sustainable sunlight energy.

Imatinib has been widely used as a selective kinase inhibitor for treating a variety of cancers, and this molecule is very hydrophobic so it is usually modified with mesylate salt in clinic to increase bioavailability. However, pH-dependent aqueous solubility and relatively high dosage of imatinib mesylate greatly reduce the clinical outcomes. To solve this problem, we developed an intestine enzyme-responsive hydrogel to efficiently encapsulate hydrophobic imatinib with long-term controlled release and enhanced intestinal permeability through oral administration. Methacrylic anhydride-modified carboxymethyl chitosan (MA-CMCS) was synthesized via amidation reaction and then MA-CMCS was crosslinked with photoinitator under UV-irradation to form a three-dimensional hydrophilic polymer network. The intestine enzyme responsiveness was endowed with imatinib-loaded hydrogel through hydrolyzation of glucosidic bond, which could achieve enzyme-triggered long-term drug release of up to 2 days. Furthermore, sodium deoxycholate was embedded into the hydrogel to synchronously open epithelial tight junctions with improved intestinal permeability. In vitro studies revealed similar lethality against colon cancer cell for both imatinib mesylate and imatinib-loaded hydrogels. Moreover, significantly enhanced in vivo tumor inhibition (6-fold higher compared to imatinib mesylate) was achieved after oral administration with imatinib-loaded hydrogels. Overall, this enzyme-responsive hydrogel could achieve long-term synchronous release of kinase inhibitor (imatinib) and tight junction permeation enhancer (sodium deoxycholate) at intestine with enhanced therapeutic efficiency, which could provide an effective approach to improve the bioavailability of hydrophobic anticancer chemodrugs with oral administration.

The hybrid Janus nanomaterials have captured considerable attention since the asymmetric structure can combine the properties of each component and display synergistic applications. However, the precise design of the specific hybrid Janus nanostructures still remains a formidable challenge. Here, we for the first time report the fabrication of novel and highly uniform inorganic/organic hybrid Janus nanotubes via disassembling the mesoporous inorganic nanoparticles (NPs)/polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) hybrid sheets, which are generated through the in situ reduction of functional metal precursors on the prepared PS-b-P4VP mesoporous scaffolds. More importantly, the internal pore size of the hybrid Janus nanotubes can be precisely tuned by readily controlling the swelling time of the PS-b-P4VP sheet-like assemblies in a selective solvent for P4VP domains, thus generating the particular inorganic/organic hybrid Janus nanotubes with adjustable inner diameter size. We believe that our finding will provide an efficient and universal route to fabricate the particular inorganic/organic hybrid nanotubes for hierarchical functional devices and nanomaterials.

Polyesters with cyclic structures in the main chain typically possess superior mechanical and thermal properties together with chemical recyclability. Ring-opening polymerization (ROP) of bridged or fused bicyclic lactones is a simple, and in most cases controlled method to synthesize polyesters with alicyclic moieties in the polymer backbone. The stereochemistry of the alicyclic structures has a great effect on the polymer properties, which can be regulated by varying the polymerization conditions. Here, we report a systematic investigation on the ROP of 2-oxabicyclo[2.2.2]octan-3-one ([2.2.2]VL) under different conditions. When initiated by n-butyl lithium (n-BuLi) or catalyzed by trifluoromethanesulfonic acid (TfOH) in the presence of benzyl alcohol, P[2.2.2]VLs containing all cis-1,4 disubstituted cyclohexane ring were obtained. However, P[2.2.2]VLs initiated by sodium methoxide (MeONa) or catalyzed by organic superbase contained both cis and trans isomeric structural units. The cis to trans transformation mechanism under these conditions was manifested, and the effect of stereochemical variations on the properties of P[2.2.2]VL was revealed. The stereoregular P[2.2.2]VLs, both cis and trans, exhibited higher crystallinity and melting temperatures (T_m) than those of the stereoirregular isomers. Finally, the degradation of P[2.2.2]VL with acid at high temperature could recover 3-cyclohexenecarboxylic acid.

High solid content CO₂-based cationic waterborne polyurethanes (CWPUs) were prepared using CO₂-polyols as soft segment and N-methyl diethanolamine (MDEA) as hydrophilic group. The resulting stable aqueous dispersion displayed a high solid content of 52% with a low MDEA loading of 3.52 wt%. This novel structural CWPU can provide excellent adhesive strength, whose T-peel strength could reach 173.48 N/5cm, 20% higher than that of ester-based cationic waterborne polyurethane (87.55 N/5cm). The CO₂-based CWPU film showed only 2 wt% swelling percentage after 240 min immersion in water, and no change was observed during its immersion in 5 wt% sodium hydroxide solution. The tensile strength of CO₂-WPUs dropped slowly to 91.2% after 480 min immersion in a 5 wt% sodium hydroxide solution, whereas that of ester-based CWPUs dropped quickly to 32% after 240 min and their mechanical properties were lost after 360 min immersion. Meanwhile, the retention of the tensile strength of the CO₂-CWPUs was 81.5% even after 720 min immersion in 10 wt% H₂O₂ solution, while it was only ca. 38% for the ester-based CWPUs. These results indicated that the cationic CO₂-based CWPU may be promising waterborne adhesive with outstanding ageing resistance due to its synergistic effect from carbonate and ether groups of CO₂-polyol structure.

Random and block copolymers of 2-methoxyethyl vinyl ether (MOVE) and 2-ethoxyethyl vinyl ether (EOVE) were synthesized within 180 s via IBVE-HCl/SnCl₄ initiating system in the presence of THF in a microflow system. The polymers can be produced continuously and efficiently with extremely narrow molecular weight distributions (M_w/M_n=1.09−1.18) even at the existence of pendant oxyethylene units. Polymerization rate can be accelerated by reducing THF to very low concentration ([THF]=50 mmol/L), reaching conversions over 60% and 70% in 60 s for EOVE and MOVE, respectively. Random copolymers poly(MOVE_100x-r-EOVE_100(1−x)) (x=0.25, 0.5, 0.75) experienced very sensitive phase separation process, of which phase separation temperature (T_ps) can be adjusted between 20 and 70 °C by controlling monomer composition. On the other hand, thermally induced phase separation of diblock copolymers poly(MOVE₁₀₀-b-EOVE₁₀₀) was not so sensitive as its random copolymer counterpart. Relatively bigger difference between phase separation temperatures of heating and cooling process (ΔT_ps) was found for diblock copolymer.

It is a daunting task to develop a promising strategy at an industrial scale for simultaneously ameliorating ductility and gas barrier performance of poly(lactic acid) (PLA) films in the application of green packaging. In this work, biaxial stretching and constrained annealing were employed to prepare transparent PLA films with superior ductility and barrier properties. The oriented nano-sized crystals induced by biaxial stretching were developed into regular α form during constrained annealing, which could not only serve as “nano-barrier wall” to impede the diffusion and dissolution of gas molecules, but also strengthen amorphous chain entanglement network as physical crosslink to enhance ductility. As a result, the as-prepared PLA films exhibited an outstanding comprehensive performance with a low oxygen and water vapor permeability coefficient of 0.733×10⁻¹⁴ cm³·cm·cm⁻²·s⁻¹·Pa⁻¹ and 3.82×10⁻¹⁴ g·cm·cm⁻²·s⁻¹·Pa⁻¹, respectively, outstanding ductility with elongation at break of 66.0%, high yield strength of 84.2 MPa, and good transparency of more than 80% at 550 nm. The new insight in the relationship between microscopic amorphous and crystalline structure and macroscopic performance is conducive to alleviating the intrinsic defects of brittle and insufficient barrier PLA films without the aid of any heterogenous modifiers, facilitating their widespread commercialization in the booming sustainable packaging market.

This research concerns the development of lithium ions conductive electrolyte from poly(vinyl butyral) (PVB) resin for use as a special interlayer film in electrochromic glass. To obtain the final PVB film with high ionic conductivity and thermal stability, a masterbatch was firstly prepared by mixing of PVB resin with lithium salt (LiClO₄) and additives in an aqueous ethanol solution. After this, the dried masterbatch were converted into final films by an extrusion process. In this study, PVB film with the highest ionic conductivity value of 4.85×10⁻⁶ was obtained when the masterbatch was diluted with the neat PVB resin at the weight ratio of 2:1 in the extruder prior to fabrication. The results from cyclic voltammetry over 100 cycles, showed that performance of the electrochromic device (ITO/WO₃/PVB electrolyte/ITO) fabricated by using the above PVB film is stable and reversible. In overall, this work demonstrates that ion conductive PVB films with compromised ionic conductivity and thermal stability can be prepared via an extrusion process without the need to modify chemical structure of PVB. This was carried out through the masterbatch approach, by introducing LiClO₄ salts into the plasticized PVB via a solution mixing process prior to converting it into a final film via the extrusion process.

In recent years, the hybrid shish-kebab structure with excellent physical properties and functionalities has attracted much attention because it provides a way of blending nanofibers with different properties into polymer matrix in a regular arrangement. It is often not easy to induce the formation of the hierarchically ordered structure for the semi-crystalline polymer in heterogeneous shish-kebab structure. A poly(lactic acid) (PLA)/poly(ε-caprolactone) (PCL) heterogeneous shish-kebab structure, i.e., the PCL crystals periodically crystallized onto PLA nanofibers, was successfully created and the interfacial crystal morphology of the PLA/PCL heterogeneous shish-kebab structure was observed using scanning electron microscopy and atomic force microscopy. NaOH aqueous solution was applied to modify the surface of the PLA nanofibers to produce adsorption sites and carboxyl groups. The total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) results demonstrated that the formation of the heterogeneous shish-kebab structure was mainly due to the hydrogen bonding interaction between the kebab and shish interface, and the growth process of the kebab crystals also promoted the crystallization of the shish fibers. This heterogeneous nanostructure of biodegradable polymers will have great applications in tissue engineering and regenerative medicine.

Forward osmosis (FO) as an energy-saving membrane process has attracted much attention in food concentration, water treatment, and desalination. Thin film composite (TFC) membrane is the most popular FO membrane, but it suffers from the internal concentration polarization (ICP), which significantly limits the water flux and FO efficiency. In this report, we demonstrate a novel and high-performing thin film nanocomposite (TFN) membrane that employs a hydrophilic interlayer composed of imogolite nanotubes (INTs) and polydopamine (PDA). The INTs can be adhered to the porous substrate by the self-polymerization of PDA, and the as-prepared PDA/INTs interlayer displays a nano-structured network with outstanding hydrophilicity. The detailed investigation was conducted to understand the relationship between the structure and property of the PDA/INTs interlayer and the morphology and performance of the TFN membrane. The TFN membrane with the PDA/INTs interlayer performs a thinner and smoother polyamide selective layer. Correspondingly, the TFN membrane shows a water flux of 18.38 L·m⁻²·h⁻¹, which is 2.18 times of the pristine TFC membrane. Moreover, the TFN membrane has a minimized structural parameter (577 μm), almost a half of that of the pristine one (949 μm). It reveals that the ICP effect of TFC membrane can be effectively alleviated by using a hydrophilic PDA/INTs interlayer. This TFN membrane with a satisfactory water permeability is promising in terms of future applications.

To investigate the feasibility of developing biobased and biodegradable thermochromic fibers, poly(lactic acid) (PLA) fibers with visual temperature indicator functionality were fabricated using a scalable melt spinning technique (spinning speed 800 m/min), where PLA and thermochromic microcapsules were used as fiber-forming polymers and color indicators, respectively. The effect of thermochromic microcapsules on the mechanical properties and reversible color-changing function of PLA fibers was systematically investigated to achieve high tenacity and sensitive color-changing function. The difference in the fiber performance was connected to changes in the multilayer structure. The results show that PLA fibers exhibit excellent tenacity of 3.7−4.7 cN/dtex and reversible and stable thermochromic behavior over 31 °C. The high fraction of mesophase within TPLA-1 fiber plays an important role in its tenacity. Meanwhile, the low-concentration of microcapsules (~1 wt%) with good dispersion could act as a nucleating agent inside the PLA matrix and contribute to the formation of microcrystals in the amorphous between primary lamellae, which is also beneficial to maintain the tenacity of the fibers. The agglomeration of high-concentration microcapsules within PLA fibers hampered the formation of mesophase, resulting in a decrease in fiber tenacity. Aside from the content of microcapsules, the agglomeration of high-concentration microcapsules (>5 wt%) is the main reason that limits the substantial increase in fiber color depth. This study opens up new possibilities for degradable thermochromic fibers produced using standard industrial spinning technology.

As an important part of semicrystalline polymer materials, polyolefin elastomers are widely used, and the in-depth analysis of their molecular chain structure information is of great significance to promote their rapid development. We show in this work an effort in characterizing a commercial polyolefin elastomer of ethylene/1-octene copolymer by a modified successive self-nucleation and annealing (SSA) technique. A small amount of linear polyethylene was blended with the ethylene/1-octene copolymer serving as nucleation agent during SSA. It turned out that a tiny fraction of linear polyethylene can significantly promote the crystallization of the copolymer during cooling from different annealing temperatures and increase the melting temperature of the fractions so that providing apparent methylene sequence length much closer to the real value than obtained by traditional SSA technique.

In this work, apigenin was chosen as a raw material to synthesize a novel epoxy monomer (DGEA), while the bio-based epoxy resin was further obtained after curing with 4,4’-diaminodiphenylmethane (DDM). The control samples were prepared by curing diglycidyl ether of bisphenol A (DGEBA) with DDM. The non-isothermal differential scanning calorimeter (DSC) method was utilized to further investigate the curing behavior and curing kinetics of the DGEA/DDM system. Despite no flame retardant active elements, the DGEA/DDM thermoset still exhibited exceptional anti-flammability. Specifically, the DGEA/DDM thermoset reached a V-0 rating in the UL-94 test and owned a high limiting oxygen index (LOI) value of 37.0%, while DGEBA/DDM resins were consumed completely in the vertical combustion test with a low LOI of 23.0%. Furthermore, the microscale combustion calorimetry (MCC) results manifested that compared with DGEBA/DDM resins, both PHRR and THR values of the DGEA/DDM resins were dropped by 84.0% and 57.6%, respectively. Additionally, the DGEA/DDM resin also presented higher storage modulus and tensile strength compared with DGEBA/DDM one. Particularly, in contrast with that of the cured DGEBA/DDM one (156 °C), the DGEA/DDM thermoset displayed an extremely high glass transition temperature (232 °C). This study breaks new ground on how to produce bio-based monomers with aromatic structures and achieve high-performance thermosetting polymers.

Development of home compostable materials based on bioavailable polymers is of high strategic interest as they ensure a significant reduction of the environmental footprint in many production sectors. In this work, the addition of thermoplastic starch to binary PLA/PBAT blends was studied. The compounds were obtained by a reactive extrusion process by means of a co-rotating twin screw extruder. Thermo-mechanical, physical and chemical characterization tests were carried out to highlight the effectiveness of the material design strategy. The compounds were subsequently reprocessed by cast extrusion and thermoforming in order to obtain products suitable for the storage of hot food. The extruded films and the thermoformed containers were further characterized to highlight their thermo-mechanical, physical and chemical properties. Thermo-rheological, mechanical and physical properties of the material and of the cast film were analyzed thoroughly using combined technique as capillary rheometer, MFI, DSC, VICAT/HDT, XRD, FTIR, UV-Vis, SEM, permeability and, lastly, running preliminary chemical inertness and biodegradation tests. Particular attention was also devoted to the evaluation of the thermo-mechanical resistance of the thermoformed containers, where the PLA / PBAT /TPS blends proved to be very effective, also presenting a high disintegration rate in ambient conditions.

A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate (polyimide) is developed. We utilized the coordination effect between palladium salts and pyridine structures to fix the palladium chloride (PdCl₂) on the surface of polymer film while the 2,6-dimethylpyridine structures formed in the specific areas under ultraviolet light guaranteed the resolution of final patterns. Simultaneous thermal reduction of PdCl₂ on the surface can be achieved in the process of thermal cyclization of the polymer substrate. As a consequence, the obtained polyimide (PI) film can be patterned with conductive copper micropatterns directly by electroless plating. In particular, we accomplished the deposition of high precision copper pattern with a minimum line width of 50 µm and minimum line spacing of 20 µm on PI thin films (thickness ~10 μm) by electroless plating. The prepared conductive copper micropatterns exhibit a low resistivity of 1.78 µΩ·cm the same as the pure block copper. And the relationship between the structures of the polymer chains and the physical properties of polymer substrates, such as the dimensional stability, mechanical and dielectric properties were also discussed in detail. This simple and novel method of patterning metal on the polymer surface does not need to achieve the catalytic metal adhesion required for electroless plating at the cost of destroying the substrate surface and avoiding the introduction of unstable interlayers. This patterning method is compatible with the current roll-to-roll production process and can be used to develop high-performance micro-integrated circuits.

There have been significant interests in recent years for incorporating dynamic bonds into polymer materials for achieving multiple functionalities, such as self-healing, recycling, stimuli-responsiveness, and so on. Nevertheless, the impact of dynamic bonds on the polymer dynamics is actually less explored. In this study, we investigate a self-healing solid-liquid elastomer (SLE), which is a dual-crosslinked network made by coupling a permanently crosslinked polydimethylsiloxane (PDMS) network with polyborosiloxane (PBS) via abundant dynamic boron/oxygen dative bonds. Proton double-quantum (DQ) NMR reveals that the crosslinking degree is reduced while the structural heterogeneity of network is enhanced with increasing PBS content, i.e., increasing the content of dynamic boron/oxygen dative bonds. Rheological experiments clearly reveal two chain relaxation modes in the SLE samples with a characteristic relaxation time of around 2.1 s and 11.8 s, corresponding to the relaxation of coupled PBS and PDMS chains, respectively. The master curves obtained from variable-temperature frequency-dependent rheological experiments also reveal enhanced heterogeneity of chain relaxation with increasing PBS content. Finally, the impact of boron/oxygen dative bonds on the Rouse dynamics is further revealed by fast-field-cycling (FFC) NMR experiments, where the spin-lattice relaxation rate (R₁) of all SLE samples follows the same power law of ${R}_{1} \left(\omega \right)\propto {\omega }^{-0.33}$. Nevertheless, the incorporation of PBS did slightly increase the energy barrier of Rouse dynamics. Our study well demonstrates a combined use of rheology and solid-state NMR spectroscopy can provide piercing insights into the interplay of crosslinking structures and dynamics of polymer materials.

This work highlights the benefits of environmental crazing for the control over the hydrophilic-lipophilic balance of glassy amorphous and semicrystalline polymers: poly(ethylene terephthalate) (PET) and biodegradable polycaprolactone (PCL). Task-oriented encapsulation of diverse commercial and natural hydrophilic (polyethyleneoxide, polyvinylpyrrolidone, gelatin) and hydrophobic guest additives (perfluoroorgano siloxanes, water-repellent impregnation) into mesoporous host polymer (PET, PCL) matrixes allows targeted control over the wettability of the resultant nanocomposite materials. Depending on the nature of the guest additive, the properties of the modified polymers can be varied from hydrophilic to hydrophobic: contact angle (CA) of PET can be adjusted from 47_┴/38_׀׀ to 130_┴/117_׀׀° (for initial PET, CA=82°) and CA of PCL from 40° to 114° (for initial PCL CA=75°). The unique benefits of environmental crazing for structural modification are related to the universal character of this approach which can be applied to a broad range of polymers and allows preparation of diverse high-performance materials with tunable hydrophilic-lipophilic balance.