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Biomimetic mineralization based on self‐assembly has made great progress, providing bottom‐up strategies for the construction of new organic–inorganic hybrid materials applied in the treatment of hard tissue defects. Herein, inspired by the cooperative effects of key components in biomineralization microenvironments, a new type of biocompatible peptide scaffold based on flexibly self‐assembling low‐complexity protein segments (LCPSs) containing phosphate or phosphonate groups is developed. These LCPSs can retard the transformation of amorphous calcium phosphate into hydroxyapatite (HAP), leading to merged mineralization structures. Moreover, the application of phosphonated LCPS over phosphorylated LCPS can prevent hydrolysis by phosphatases that are enriched in extracellular mineralization microenvironments. After being coated on the etched tooth enamel, these LCPSs facilitate the growth of HAP to generate new enamel layers comparable to the natural layers and mitigate the adhesion of Streptococcus mutans. In addition, they can effectively stimulate the differentiation pathways of osteoblasts. These results shed light on the potential biomedical applications of two LCPSs in hard tissue repair. [ABSTRACT FROM AUTHOR]

Abstract Biomimetic mineralization based on self‐assembly has made great progress, providing bottom‐up strategies for the construction of new organic–inorganic hybrid materials applied in the treatment of hard tissue defects. Herein, inspired by the cooperative effects of key components in biomineralization microenvironments, a new type of biocompatible peptide scaffold based on flexibly self‐assembling low‐complexity protein segments (LCPSs) containing phosphate or phosphonate groups is developed. These LCPSs can retard the transformation of amorphous calcium phosphate into hydroxyapatite (HAP), leading to merged mineralization structures. Moreover, the application of phosphonated LCPS over phosphorylated LCPS can prevent hydrolysis by phosphatases that are enriched in extracellular mineralization microenvironments. After being coated on the etched tooth enamel, these LCPSs facilitate the growth of HAP to generate new enamel layers comparable to the natural layers and mitigate the adhesion of Streptococcus mutans. In addition, they can effectively stimulate the differentiation pathways of osteoblasts. These results shed light on the potential biomedical applications of two LCPSs in hard tissue repair.

• Novel phosphonated DDS-based epoxy hardeners induced higher thermal stability as well as latent curing potency for the epoxy resin networks. TGA results showed that either ER/Dicy/DDS-DPPC or ER/Dicy/DPPC-DDS-DPPC exhibited higher char yields and lower degradation rates comparing to the cured ER/Dicy. In addition, the flame-retardancy induction was preliminarily established by the hardeners to the thermosets and approved by cone calorimetry. Therefore, it is a generally impressive and facile approach to modify latent flame-retardant curing agents for ER by modifying DDS with DPPC. Taking advantage of the features, these one-pack flame-retardant epoxy materials can create a greater chance of several applications. Epoxy resins (ER) along with their curing agents and flame retardant additives are preferred to be formulated as a one-pack material. Increasing viscosity during storage and operation is a complicated problem for one-pack material. To resolve the above-mentioned problem, we conducted a synthesis on new phosphorus-containing curing agents of 4,4-diamino diphenyl sulfone (DDS) and diphenyl phosphoryl chloride (DPPC) to be taken advantage of alongside a combination of dicyandiamide (Dicy). The chemical structure of both of the synthesized compounds derived from DDS (i.e., DDS-DPPC and DPPC-DDS-DPPC) were characterized by FTIR, as well as 1H-, 13C- and 31P-NMR spectroscopies. Latency and curing behavior of ER/Dicy/DDS-DPPC and ER/Dicy/DPPC-DDS-DPPC were studied by viscometry and differential scanning calorimetry (DSC). The compounds' cured products' thermal properties went through an investigation via DSC, thermogravimetric analysis (TGA), and cone calorimetry. The results revealed that the novel phosphonated DDS-based epoxy hardeners induced higher thermal stability and latent curing potency for the ER networks. TGA results showed that either ER/Dicy/DDS-DPPC or ER/Dicy/DPPC-DDS-DPPC exhibited higher char yields and lower degradation rates than that of the cured ER/Dicy's. With the incorporation of new synthesized curing agents into epoxy resin, ER/Dicy/DDS-DPPC and ER/Dicy/DPPC-DDS-DPPC samples achieved UL-94 V-1 and V-0, respectively. During combustion, synthesized curing agents decomposed to produce phosphorus-containing compounds to form protective char layers in the condensed phase, and generated phosphorus-containing radicals which quenched the active radicals in the gaseous phase. DDS-DPPC and DPPC-DDS-DPPC demonstrated a bi-phase flame retardant effect. Moreover, the flame-retardancy induction was preliminarily established by hardeners to the thermosets. Therefore, it is a generally impressive and facile approach to modify latent flame-retardant curing agents for ER by modifying DDS employing DPPC. Taking advantage of the features, these one-pack flame-retardant epoxy materials can create a greater chance of multiple applications. Furthermore, the samples' mechanical properties were evaluated by use of dynamic mechanical thermal analysis and flexural tests. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Membranes of phosphonated polyphenylsulfone with functionalization degree up to 88–106% were prepared by reaction in the presence of Pd(0)-complexes. Membranes of phosphonated and sulfonated polyphenylsulfone were also prepared by sulfonating previously phosphonated polyphenylsulfone. The membrane proton conductivities were evaluated by impedance spectroscopy at the temperature range between 50 and 150°C. While sulfonated membranes had higher proton conductivity at 100% relative humidity, they swell much more than the phosphonated films in water and have a much higher permeability to water and methanol. Phosphonated films are thermally more stable. [Copyright &y& Elsevier]