پديد آورنده :
كاظمي دوچقايي، امير
عنوان :
بررسي اثر هم افزايي نانو الياف سلولزي و ذرات ليگنين استخراج شده از كاه گندم و انجام عمليات حرارتي بر خواص فيزيكي- مكانيكي فيلم پلي (وينيل الكل)
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
پليمر (فرآورش)
محل تحصيل :
اصفهان : دانشگاه صنعتي اصفهان
صفحه شمار :
دوازده، 92 ص. : مصور، جدول، نمودار
استاد راهنما :
طيبه بهزاد
استاد مشاور :
كيخسرو كريمي
توصيفگر ها :
پيش فرآوري , كاه گندم , ليگنين , بيوكامپوزيت , پلي (وينيل الكل) , نانو الياف سلولزي , عمليات حرارتي , بسته بندي غذايي
استاد داور :
سعيد نوري خراساني، مهدي كديور
تاريخ ورود اطلاعات :
1399/08/05
رشته تحصيلي :
مهندسي شيمي
تاريخ ويرايش اطلاعات :
1399/08/10
چكيده فارسي :
9 14 4 3 پيش فرآوري حالل آلي و استخراج ليگنين 54 4 4 مشخصهيابي ليگنين استخراج شده 84 4 5 مشخصهيابي فيلمها 84 4 5 1 عبور پييري نور 35 4 5 2 ساختار شيميايي فيلمهاي پليمري 75 4 5 3 خواص مكانيكي 26 4 5 4 خواص مربوط به آب 96 4 5 5 ريز ساختار فيلم بيوكامپوزيتي 27 4 5 6 پايداري گرمايي 67 4 5 7 مطالعهي سينتيكي عمليات حرارتي 87 4 5 8 زيست تخريب پييري در خاك 08 4 5 9 آزمون بستهبندي غيايي فصل پنجم نتيجه گيري و پيشنهادها 18 5 1 مقدمه 28 5 2 نتايج كلي 48 5 3 پيشنهادها 68 منابع 39 چكيده انگليسي
چكيده انگليسي :
93AbstractIn this study wheat straw was treated with 50 v v ethanol water solution at 180 and 215 psifor 45 min The obtained pulp yield was 54 1 containing 9 1 of acid insoluble lignin and 7 5 of ash After the precipitation of the organosolv liquor 0 74 g of lignin from the total 1 7 g of ligninin wheat straw was extracted Isolated lignin contained 90 1 of acid insoluble lignin and 2 1 ofash indicating its high purity The structure of lignin was investigated by FTIR and 1H NMRspectroscopy confirmed the presence of G S and H monomeric subunits alongside aromaticprotons phenolic hydroxyls carboxylic acids and aldehydes Using the isolated lignin polyvinylalcohol 1 5 lignin polyvinyl alcohol 3 lignin polyvinyl alcohol 3 lignin 1 cellulose nanofibers and crosslinked polyvinyl alcohol 3 lignin biocomposite films were fabricated numbers are in w w with respect to polyvinyl alcohol The presence of lignin in the films led to almost 100 UV radiation filtering FESEM images of a dried 10 L drop of lignin dispersion in water and the surfaceof polyvinyl alcohol 3 lignin films showed nanoparticles with average diameter of less than 100 nmand the homogenous distribution of lignin particles in the matrix respectively ATR FTIR of thebiocomposite films showed the existence of physical hydrogen bonding between the matrix and thereinforcement phases and also confirmed the formation of ester bonds between citric acid andhydroxyl containing polymeric components Results of the mechanical tensile tests stated thatincorporation of lignin cellulose nanofibers and crosslinking increased elastic modulus by 97 212 and 396 respectively Water contact angel reached to 52 50 and 67 after addition of lignin cellulose nanofibers and performing heat treatment respectively The concurrently addition of ligninand cellulose nanofibers increased the initial thermal decomposition temperature of polyvinyl alcoholfilms from 228 to 273 Moreover lignin addition developed the biodegradability of the films insoil by increasing weight loss from 31 for neat polyvinyl alcohol films to 56 for reinforcedbiocomposites Furthermore biocomposite films containing lignin and cellulose nanofibers showedpotential application for fatty food packaging according to overall migration value of 34 5 mg kg which was lower than the European standard of 60 mg kg Keywords pretreatment wheat straw lignin biocomposite poly vinyl alcohol cellulosenanofibers heat treatment food packaging
استاد راهنما :
طيبه بهزاد
استاد مشاور :
كيخسرو كريمي
استاد داور :
سعيد نوري خراساني، مهدي كديور
