| 摘要 |
Surface-modified cellulose microfibrils with the ratio L/D m ore than 20, preferably more than 100 and middle ratio 1 - 50 nm, where L is a length of a microfibril and D is its middle diamete r. At least 25 % from the number of hydroxyl groups in the surfac e of microfibrils are esterified by at least one organic compound containing at least one group able to react with hydroxyl groups of cellulose. In consequence to that this organic compound conta ins acetyl groups, such as for example acetic acid, the said micr ofibrils are used as a toughening agent in the material containin g acetylcellulose as a polymeric matrix. The composite material, filled by this way, can be shaped into the films, moldings, fiber s or yarns. |
