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The organic‐inorganic hybrid fluorescent hyperbranched polymer, including hyperbranched polysiloxane and hyperbranched polyborate, have attracted much attention due to their excellent optical properties and wide range of applications. Hyperbranched polysiloxane and polyborates, prepared by introducing Si or B elements into organic polymer chains at the molecular level through rational molecular design and novel synthesis methods, exhibit outstanding photophysical properties as an indispensable branch of organic‐inorganic hybrid fluorescent materials. Herein, this review highlights the recent research progress on hyperbranched polysiloxanes and hyperbranched polyborates, including strategies for regulating their emission wavelengths, quantum yields, and fluorescence lifetimes, potential emission mechanisms, and various applications. Finally, some challenges and promising future directions in the field of organic‐inorganic hybrid fluorescent polymers are summarized. Organic‐inorganic hybrid materials combine the superior photostability of inorganic components with the processability of organic polymers. This review summarizes and discusses recent advances in organic‐inorganic hybrid fluorescent materials, including hyperbranched polysiloxanes and hyperbranched polyborates, in terms of preparation methods, regulation strategies for optical properties, and applications. Furthermore, the challenges associated with such materials and their potential future research directions are discussed.

The loose and porous structural nature of silicate cultural heritages makes them vulnerable to environmental changes. After thousands of years exposure, many of them are seriously degraded. Consolidation using certain conservation material is one of the most common methodologies to protect them. However, the vapor permeability of the relics often decreases significantly because conservation material fills the pores or changes the hydrophilicity of the relics, both blocking the vapor transportation. In this work, a novel hyperbranched polysiloxane is synthesized and its potential as conservation material for silicate cultural heritages is examined using sandstones from Yungang grottoes as mockup samples. The hyperbranched structure can lead to the formation of continuous, crack-free, and breathable network, which provides required reinforcement and remains most of the vapor permeability of the treated stone. Our results show that the as-prepared hyperbranched polysiloxane is highly potential for sandstone relics conservation, such as Yungang grottoes. Graphical abstract Highlights Hydroxy and amine terminated hyperbranched polysiloxane (HB-PolySi) and its linear analogue (L-PolySi) are synthesized and evaluated for cultural heritage conservation. When they are used to restrengthen aged sandstones, HB-PolySi shows better mechanical reinforcement than L-PolySi due to its hyperbranched structure. After application, HB-PolySi also remains over 95% of the original vapor permeability of the stone.

Owing to its designability and intrinsic fluorescence, non‐conjugated hyperbranched polysiloxane (HBPSi) has attracted widespread attention in biological filed, while it is still severely restricted by low fluorescence efficiency. So, in this paper, we introduced disulfide into HBPSi improving their luminescence properties and synthesized different molecular weight HBPSi (P1, P2, and P3). Surprisingly, P1 exhibited ultrahigh quantum yield up to 47.81%. Meanwhile, experiments applied with theoretical calculations were employed to explore the fluorescence mechanism, which is attributed to efficient restricting of non‐radiative decay by clusteroluminogens formed with the cooperation of hyperbranched structure and double hydrogen bonding. In addition, the biocompatibility of P1 was verified by co‐culture with MC3T3‐E1 and P1 lighted up mouse fibroblast cells without fluorescent dyes. This work designed a novel fluorescent polymer with ultrahigh fluorescence quantum yield and cell imaging ability, which is promising in visualization diagnosis and treatment of tumor. Hyperbranched polysiloxane (P1) with high quantum yield up to 47.81% was synthesized, in which the groups of –Si–O–, –C=C–, –C(O)O–, and –S–S– in the aggregate work together to form clusteroluminogens to limit non‐radiative decay. In addition, P1 lights up osteoblasts and its biosafety is validated.

In order to obtain a polymer with good biocompatibility and aggregation induced luminescence, amino group was introduced into hyperbranched polysiloxane (HBPSi) structure by one-step transesterification, and two HBPSi containing terminal amino group (HBPSi-NH 2 ) were prepared. It was worth noting that both of them exhibit good luminescence characteristics. To further study the relationship between their structure and luminescence intensities, the structure and molecular weight distribution of these two HBPSi-NH 2 were studied by nuclear magnetic resonance spectroscopy (NMR), fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC), the luminescence properties of the prepared HBPSi-NH 2 were characterized by fluorescence spectroscopy (PL). The results showed that the luminescence intensity of HBPSi-NH 2 was affected by the molecular weight and dispersion. HBPSi-NH 2 with low molecular weight can emit strong fluorescence, and in the good solvent (tetrahydrofuran, THF), the HBPSi-NH 2 exhibit strong dispersion and leads to the weakest luminescence performance, while in bad solvent, it can lead to the weak dispersion and the strongest luminescence performance.

The branching and cross-linking of siloxane polymers are important processes in silicone technology. A new type of such a process has been developed, which is a self-restructuring of linear polyhydromethylsiloxane (PHMS). This process involves the reorganization of the PHMS to form a highly branched siloxane polymer or finally a cross-linked siloxane network. It occurs through the transfer of a hydride ion between silicon atoms catalyzed by tris(pentafluoromethyl)borane. Its advantage over existing branching and cross-linking reactions is that it runs at room temperature without a low-molecular-weight cross-linker in the absence of water, silanol groups, or other protic compounds and it does not use metal catalysts. The study of this process was carried out in toluene solution. Its course was followed by 1H NMR, 29Si NMR and FTIR, SEC, and gas chromatography. A general mechanism of this new self-restructuring process supported by quantum calculations is proposed. It has been shown that a linear PHMS self-restructured to a highly branched polymer can serve as a pure methylsiloxane film precursor.

A novel phosphorous/silicon hybrid containing active amino was synthesized by bisphenol F epoxy resin modified by 0-(2,5-Dihydroxyphenyl)−10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide (ODOPB) and hyperbranched polysiloxane (APTMS-HPSi). At first, APTMS-HPSi was synthesized by a simple reaction among aminoethylamino propyltrimethoxy silane (APTMS) and tripropylene glycol (TPG). ODOPB was used to modify bisphenol F epoxy resin. Then add different content of APTMS-HPSi to the phosphorus-containing modified epoxy resin (P-EP). Fourier Transform Infrared (FTIR) Spectroscopy was used to characterized the chemical structure of APTMS-HPSi. The effects of APTMS-HPSi content on key properties was systemically investigated. Results showed that the addition of APTMS-HPSi and ODOPB effectively improve the toughness and liquid oxygen compatibility. With the increase content of APTMS-HPSi, char yield and limited oxygen index (LOI) value of the cured resin increased, and the liquid oxygen sensitivity coefficient (IRS) decreased. The elongation at break was increased 45.32% by only 6wt% loading with APTMS-HPSi in epoxy resin, and at the same time the IRS of the modified resin was reduced from 7% to 0%. When the addition amount was 6wt%, the fracture elongation, impact strength and fracture toughness K IC were increased by 52.1%, 81.8% and 54.3% respectively. Therefore, adding phosphorus and hyperbranched polysiloxane to the resin can improve the liquid oxygen compatibility and toughness of the epoxy resin at the same time.

To improve the thermal resistance properties of epoxy (EP) resin, a novel hybrid silicon dioxide (F-SiO 2 ) was prepared via a convenient sol–gel process, while the fluorosilane coupling agent 3,3,3-trifluoropropyl(trimethoxy)silane and tetraethoxysilane (TEOS) were employed as the raw materials. The prepared F-SiO 2 was then used as modifier phase to blend with EP to prepare new polymer alloys F-SiO 2 /EP. The thermal properties of cured F-SiO 2 /EP resins were investigated by thermogravimetry (TG), and their dielectric properties were also researched. The results showed that both the thermal conductivity of F-SiO 2 /EP increased effectively with reasonable addition of F-SiO 2 , whereas their dielectric properties were not reduced significantly. The enhancement of thermal conductivity of F-SiO 2 /EP was owning to the excellent ability of F-SiO 2 to absorb heat, as while as the good synergy between fluorine and silicon.

Although hyperbranched polysiloxanes have been extensively studied, they have limited practical applications because of their low glass transition temperatures. In this study, we synthesized benzocyclobutene-functionalized hyperbranched polysiloxane (HB-BCB) via the Piers-Rubinsztajn reaction. The synthesized material was cured and crosslinking occurred at temperatures greater than 200 °C, forming a low-k thermoset resin with high thermostability. The structure of the resin was characterized using nuclear magnetic resonance (NMR) spectroscopy, viz. 1 H NMR and 13 C NMR spectroscopy. 29 Si NMR spectroscopy was used to calculate the degree of branching. Differential scanning calorimetry, dynamic mechanical analysis, and thermogravimetric analysis revealed that the cured resin possesses good high-temperature mechanical properties and exhibits a high thermal decomposition temperature (T d5  = 512 °C). In addition, the cured resin has a low dielectric constant (k = 2.70 at 1 MHz) and low dissipation factor (2.13 × 10 −3 at 1 MHz). Thus, the prepared resin can function as a low-k material with excellent high-temperature performance. These findings indicate that the performance of crosslinked siloxane is significantly attributed to the introduction of BCB groups and the formation of the highly crosslinked structure.

A novel hyperbranched polysiloxane functionalized graphene oxide (HPBSi-GO) containing abundant primary amine, tertiary amine and hydroxyl groups was designed and successfully synthesized though efficient “grafting to” method. The as-synthesized HBPSi-GO was confirmed by FT-IR, XPS and AFM. Moreover, the HPBSi-GO was incorporated into epoxy (EP) resin matrix to fabricate HPBSi-GO/EP composites. The results showed that the HPBSi-GO has better dispersibility than that of unmodified GO in EP matrix. Interestingly, the mechanical and frictional properties of HPBSi-GO/EP composites were simultaneously superior to those of neat epoxy resin. AFM and TOM results revealed that the good properties mainly attributed to the unique inorganic–organic structure of HBPSi-GO, as well as the good interfacial adhesion between HBPSi-GO and EP matrix.

A new UV-curable hyperbranched silicone epoxy acrylate resin was synthesized, and two kinds of carbon-based components, graphite and graphene, were applied as conductive materials. An ultraviolet-curing coating was successfully synthesized with using epoxy acrylate (EA) as oligomer, butyl acrylate (BA), and hyperbranched polysiloxane (HPSi) as monomers, benzoin dimethyl ether (DMPA), and benzophenone (BP) as photo-initiators, triethanolamine (TEA) as photo-activator, and other auxiliaries. In this work, the UV-curing efficiency and cured performance, together with the effect of different conductive fillers and the amount of conductive filler on the integrated performance of the composites, are investigated. The results show that as the HPSi content increases, the curing time is shortened. At the addition amount of 7.5%, it reaches the best conductivity, and at the addition amount of 10%, the corrosion resistance after curing is the best. However, the maximum tensile strength of 10.4% is obtained at 0.75 graphene. The FE-SEM micrographs of the UV-curable conductive coating show that with increasing incorporation of graphene into the substrate, the fractured surface of a rough surface changes to smooth one. Thermal properties of the films investigated using TGA curves indicate that graphene-doped conductive adhesive film (315.1 °C) possesses much higher heat resistance than that of graphite-doped conductive adhesive film.