2 results about "Methyl phenyl polysiloxane" patented technology

This invention discloses a low-cost, rapidly prepared neutron / gamma-discriminating polysiloxane scintillator and its preparation method. The polysiloxane scintillator comprises a matrix, a primary fluorescent dye, a secondary fluorescent dye, and a crosslinking agent. The scintillator matrix is ​​a copolymer of methylphenyl polysiloxane and polyphenyl-(dimethylsiloxane), the primary fluorescent dye is 2,5-diphenyloxazole (PPO), the secondary fluorescent dye is 7-diethylamino-4-methylcoumarin (MDAC), and the crosslinking agent is 1,3-divinyl,1,3-diphenyl,1,3-dimethylsiloxane. The resulting polysiloxane scintillator possesses neutron and gamma discrimination capabilities, good radiation resistance, stability, and low cost, making it suitable for use in neutron detectors.

The application relates to the technical field of defoaming agent preparation, in particular to a high-content organic silicon defoaming agent composition for a high-temperature and high-shear system. The high-content organic silicon defoaming agent composition is prepared by the following steps: firstly, octamethylcyclotetrasiloxane, tetramethyltetraphenylcyclotetrasiloxane and hydrogen-containing polymethylsiloxane are copolymerized to construct a methylphenyl polysiloxane skeleton; secondly, acetyl-terminated allyl epoxy oxirane / epoxy propane copolyether and allyl glycidyl ether are introduced step by step; then, the obtained product is sequentially reacted with N,N-diethyl-1,3-propanediamine, phenyl isocyanate, diisopropylamine and maleic anhydride to obtain a urea-based / esterified modified polysiloxane; finally, the urea-based / esterified modified polysiloxane is compounded with methylphenyl silicone oil, dimethyl silicone oil, hydrophobic fumed silica and precipitated silica to obtain the high-content organic silicon defoaming agent composition. The obtained defoaming agent has the advantages of instant defoaming, excellent sustained defoaming, strong shear resistance, storage stability and no floating oil in a high-temperature circulating cleaning liquid system, a high-speed sand mill slurry system and the like.