Preparation of hybrid cyanate ester resin in the presence of polysilazane and its properties

Abstract

A hybrid cyanate ester resin containing polysilazane was prepared via the prepolymerization of bisphenol-A dicyanate ester monomer (BADCy) in the presence of polysilazane (PSZ) under low temperature conditions in a short period of time. Fourier transform-infrared (FT-IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy reveal that the polymerization reaction of BADCy can be carried out in the presence of PSZ to obtain a hybrid resin below 100°C and polymethylsilazane (PHS) exhibits an improved prepolymerization effect when compared to polydimethylsilazane (PMS). FT-IR spectroscopy and gel permeation chromatography (GPC) showed that the prepolymerization degree of the PHS/BADCy resin increased upon increasing PHS mass fraction from 0 to 12 wt%, polymerization temperature from 60 to 100°C and polymerization time from 0 to 4 h. The PHS/BADCy hybrid resins samples were prepared and their process properties were investigated by rheometry and Differential scanning calorimetry (DSC). The results indicated that their viscosity was <10 Pa.s in the temperature range of 60–130°C, and the initial curing temperature and curing exothermic enthalpy were 121.9°C and 358.9 J/g, respectively. Furthermore, the cured PHS/BADCy resin possesses excellent thermal and mechanical properties, the 5% weight loss temperature (Td5) and glass transition temperature (Tg) were 424–441°C and 273–282°C, respectively. The cured PHS/BADCy resin with 4 wt% PHS showed the highest flexural strength of 146 MPa and flexural modulus of 4.1 GPa.

Polysilazane hybrid phenolic resin ceramic aerogels with excellent electromagnetic wave absorption performance

“…Polysilazane supplied by our laboratory, 44 which was prepared from methyl vinyl dichlorosilane and vinyl trichlorosilane via an ammonolysis method (Figure S1). 45,46 Phenolic resin was acquired from Shanghai Aladdin Biochemical Technology Co., Ltd., diisopropylbenzene peroxide (DCP) was obtained from Shanghai Lingfeng Chemical Reagent Co., Ltd., dimethylformamide (DMF) was purchased from Shanghai McLean Biochemical Technology Co., Ltd., and dioxane was obtained from Shanghai Titan Technology Co., Ltd. All raw materials were used as received without any further purification.…”

“…Polysilazane supplied by our laboratory, 44 which was prepared from methyl vinyl dichlorosilane and vinyl trichlorosilane via an ammonolysis method (Figure S1). 45,46…”

Cure behavior and mechanism of cyanate ester with aromatic amines at room temperature

“…Recently, many scholars have been committed to studying how to cure cyanate at low temperature for a short time. [10][11][12][13][14][15] Endo et al investigated the reaction of aliphatic amines and cyanate esters at low temperature and confirmed the formation of intermediates during the reaction based on NMR and FT-IR spectroscopy. Wang et al found that benzoxazine and cyanate gel after 24 h at 30°C in solution and proposed a catalytic mechanism for the polymerization of cyanate by the tertiary amines in benzoxazine.…”

Curing kinetics and mechanical properties of cyanate ester/hyperbranched benzoxazine copolymers

“…As a high performance resin, CE resins are widely used in high performance radome, electronic packaging materials, aerospace industry, and other fields due to their excellent thermal properties, dielectric properties, flame retardancy, and low water absorption 1,2 . However, CE resin has a fatal defect in that the curing temperature is very high, above 300°C, which cannot meet the industrial demands 3,4 .…”

“…As a high performance resin, CE resins are widely used in high performance radome, electronic packaging materials, aerospace industry, and other fields due to their excellent thermal properties, dielectric properties, flame retardancy, and low water absorption. 1,2 However, CE resin has a fatal defect in that the curing temperature is very high, above 300 C, which cannot meet the industrial demands. 3,4 At the same time, due to the highly symmetrical structure of the triazine ring produced by the trimerization reaction of CE resin, the CE resin not only has a large volume shrinkage but also exhibits brittleness, which seriously affects the application of the CE resin in various fields.…”