私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

當前位置:> 首頁 > 論文著作 > 正文
Highly fibrillated and intrinsically flame-retardant nanofibrillated cellulose for transparent mineral filler-free fire-protective coatings
作者:Tong CC, Zhang S, Zhong TH, Fang ZP, Liu HZ*
關鍵字:Nanofibrillated cellulose, Quaternization, Borylation, Flame retardancy, Fire-protective coating
論文來源:期刊
具體來源:Chem. Eng. J., 2021.5, 419: 129440
發表時間:2021年
Developing functional nanocellulose-based materials while well maintaining their inherent excellent attributes is crucial to achieve the value-added applications. However, their inherent flammability largely limits their potential applications in many fields with fire-safety concerns. In this work, an intrinsically flame-retardant nanofibrillated cellulose (NFC) was successfully prepared from kraft and unbleached bamboo pulps, respectively, via a three-step strategy involving quaternized pre-treatment, mechanical disintegration and subsequent borylation. TEM images show that the well-defibrillated cellulose nanofibrils with an average diameter of 5–9 nm were successfully obtained. The morphological, physicochemical, mechanical, thermal and flame-retardant characteristics of NFC suspensions, and their resulting films were systematically characterized. The borylated NFC film from the kraft pulp (B/Q-NFC) exhibits remarkably improved char yield while retaining high degree of fibrillation, optical transparency and mechanical properties of the Q-NFC one. Despite relatively lower optical transmittance and tensile strength, the lignin-containing NFC (L-Q-NFC) from unbleached pulp exhibits better thermal stability and outstanding UV-shielding function. Flame-retardant properties of borylated NFC samples were comprehensively investigated in terms of microscale combustion calorimetry (MCC), limiting oxygen index (LOI), vertical burning, and cone calorimetry tests. A synergistic effect was noted between B and lignin species in promoting flame resistance of Q-NFC matrix (L-B/Q-NFC). When being used as flame-retardant coatings on the filter paper and PET film, both of borylated NFC films display excellent flame-retardancy and smoke-suppression effects. In combination with of surface and bulk chemical composition analysis, TGA results as well as oxygen- permeability and thermal diffusivity measurements, the flame-retardant mechanism of borylated NFC films was elucidated. These favorite features enable them to act as sustainable fire-protective coatings for many fields such as thermal insulation, electronics, separators for lithium-ion battery, etc.
主站蜘蛛池模板: 深圳市| 芦溪县| 仙游县| 福州市| 成武县| 牟定县| 丰镇市| 阜南县| 青岛市| 区。| 凤山市| 积石山| 河池市| 阿尔山市| 棋牌| 安徽省| 刚察县| 留坝县| 申扎县| 色达县| 晋城| 宁陵县| 隆德县| 安庆市| 遵化市| 五台县| 沁源县| 安义县| 平舆县| 宁明县| 广汉市| 安平县| 北川| 兰西县| 阳城县| 称多县| 林芝县| 太康县| 涿鹿县| 崇礼县| 宁陕县|