A hybrid polyborosiloxane was synthesized and the effect of boron concentration on the Si–O : B weak bonding of polyborosiloxane was investigated mainly using FTIR and dynamic rheology.

Thermal ageing studies over relative high temperature range (from 250°C to 85°C) have been conducted on polydimethylsiloxane (PDMS) rubber with the aim of investigating ageing behavior. Tensile elongation, compression set and creep measurements are introduced to monitor the ageing process. Time temperature superposition is performed and the linear trends are found in the Arrhenius plots for all the approaches, revealing an identical process dominates the degradation process. Activation energies are found to be depended on the methods used, which are 88.5 kJ/mol for tensile tests, 67.7 kJ/mol for compression set measurements and 75.3 kJ/mol for creep measurements. The phenomenon that activation energy obtained from tensile elongation is always higher than other approaches is rationalized by the sensitive modification of thermal degradation on the rubbery network. Moreover, correlations between the results from different approaches have been examined. The linear relationships have been found between tensile elongation and creep or compression set measurements for the three methods are all influenced by the network structure.

Dative bonds are crucial for room-temperature phosphorescence (RTP) of metal complexes, which are nevertheless of high cost and toxicity. Here, we develop a class of amorphous RTP polymers based on nonmetal dative bonds through copolymerizing vinylphenyl­boronic acid and acrylamide derivatives. Nonmetal dative bonds, formed between boron and nitrogen/oxygen atoms, can populate triplet excitons through charge transfer and immobilize phosphors to suppress nonradiative relaxation, leading to effective RTP lifetime in air. Moreover, the dynamic nature of the dative bonds enables self-healing and anticounterfeiting abilities of the RTP polymers. The concept of designing nonmetal dative bonds can widely expand the horizon and application of RTP polymers.

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