The effects of fiber silane modification on the mechanical performance of chopped basalt fiber/ABS composites

The purpose of this study was to examine the effects of silane coupling agent modifications on the mechanical performance of the basalt fiber (BF)-reinforced acrylonitrile–butadiene–styrene (ABS) composites. Three different silane coupling agents were used. The mechanical properties of the composites were determined by the tensile, flexural, impact tests, and dynamic mechanical analysis (DMA). According to the test results, the tensile strength increased with the use of (3-aminopropyl) triethoxysilane (AP) and 3-(trimethoxysilyl) propylmethacrylate (MA), while the use of (3-glycidyloxypropyl) trimethoxysilane (GP) reduced the tensile strength. All the silane modifications improved the flexural strength and modulus and the highest improvement was achieved with the use of AP. No remarkable difference was observed in impact properties with the use of silane coupling agents. The addition of BF significantly improved the elastic modulus of the ABS regardless of the modification type, while the further improvements were achieved through the use of AP and MA. In brief, AP showed the highest performance among the studied silane coupling agents due to the covalent bond formation between the amino group of AP and the nitrile group of styrene–acrylonitrile (SAN) matrix. © The Author(s) 2019

Preparation of cellulosic fibers with biological activity by immobilization of trypsin on periodate oxidized viscose fibers

In this study, a biologically active fibrous material was designed by immobilizing trypsin on viscose fibers. The viscose yarn was first oxidized with sodium periodate to produce aldehyde groups and then employed as a support for subsequent immobilization of trypsin through bovine serum albumin. The oxidation by sodium periodate caused changes in the chemical and physical properties of the modified yarn samples, which were evaluated by determining the aldehyde group content, fineness and tensile strength of yarn. The viscose fibers oxidized under the most severe conditions (0.4 % NaIO4, 360 min) exhibited the maximum amount of introduced aldehyde groups (1.284 mmol/g), but also the highest decrease in tensile strength. The trypsin activity was assayed with N-alpha-benzoyl-DL-arginine p-nitroanilide hydrochloride, whereas the amount of bound trypsin was determined by Bradford method. Trypsin immobilized on oxidized viscose yarn retained 97.3 and 83.8 % of the initial activity over 60 days of storage at 4 and 25 A degrees C, respectively, and remained firmly attached to the carrier. The potential application of obtained bioactive fibers is in the treatment of wounds