具有疏水表面的高强度再生纤维素复合薄膜的制备与微观结构
|
摘要
将纤维素纳米晶(CNCs)混入纤维素溶液中,经过凝胶化再生制得具有疏水表面的高强度再生纤维素复合薄膜。扫描电镜表明CNCs与再生纤维素基体具有良好的相容性。X射线衍射研究发现CNCs的加入使复合薄膜纤维素I型晶含量提高。表面水接触角测试表明CNCs会提高复合薄膜表面亲水性,经过硅烷化改性之后复合薄膜表面呈疏水性,其水接触角约为105°。CNCs的加入使复合薄膜的拉伸强度达到92.0 MPa,相比于纯再生纤维素薄膜(62.7 MPa)提升了46.7%。弹性模量也从3466 MPa提高至6025 MPa,提升了约1.6倍。CNCs的加入能提高再生纤维素薄膜起始热降解温度和热降解峰值温度。
High strength regenerated cellulose composite films with hydrophobic surface were prepared after the gelation regeneration of mixture of cellulose nanocrystals and cellulose matrix. The structures of the composite films were studied by SEM. It is found that the CNCs have a good compatibility with the regenerated cellulose matrix. It is also found that the addition of CNCs increases the content of cellulose crystal of the composite films by XRD. The surface water contact angle test shows that the addition of CNCs enhances the surface hydrophilicity of the composite films. After silylation modification, the surface of the composite films is hydrophobic, and its water contact angle is about 105°. The addition of CNCs results in the tensile strength of regenerated cellulose films of 92.0 MPa, which is 46.7% higher than that of the pure regenerated cellulose film(62.7 MPa). Elastic modulus also increases from 3466 MPa to 6025 MPa, an increase of about 1.6 times. The thermally degrade beginning temperature and the maximum mass loss rate temperature are increased by adding CNCs.
High strength regenerated cellulose composite films with hydrophobic surface were prepared after the gelation regeneration of mixture of cellulose nanocrystals and cellulose matrix. The structures of the composite films were studied by SEM. It is found that the CNCs have a good compatibility with the regenerated cellulose matrix. It is also found that the addition of CNCs increases the content of cellulose crystal of the composite films by XRD. The surface water contact angle test shows that the addition of CNCs enhances the surface hydrophilicity of the composite films. After silylation modification, the surface of the composite films is hydrophobic, and its water contact angle is about 105°. The addition of CNCs results in the tensile strength of regenerated cellulose films of 92.0 MPa, which is 46.7% higher than that of the pure regenerated cellulose film(62.7 MPa). Elastic modulus also increases from 3466 MPa to 6025 MPa, an increase of about 1.6 times. The thermally degrade beginning temperature and the maximum mass loss rate temperature are increased by adding CNCs.
引文
[1] Frackowiak S,Ludwiczak J,Leluk K.Man-made and natural fibres as a reinforcement in fully biodegradable polymer composites:a concise study[J].J.Polym.Environ.,2018,26:4360-4368.
[2] Kyutoku H,Maeda N,Sakamoto H,et al.Effect of surface treatment of cellulose fiber (CF) on durability of PLA/CF bio-composites[J].Carbohydr.Polym.,2019,203:95-102.
[3] Xie X L,Zhong G J,Li Z M,et al.A nacre-mimetic superstructure of poly (butylene succinate) structured by using an intense shear flow and ramie fiber as a promising strategy for simultaneous reinforcement and toughening[J].J.Mater.Chem.,A,2017,5:22697-22707.
[4] Li J Y,Nawaz H,Zhang J M,et al.All-cellulose composites based on the self-reinforced effect[J].Compos.Commun.,2018,9:42-53.
[5] Qi H S,Cai J,Zhang L N,et al.Properties of films composed of cellulose nanowhiskers and a cellulose matrix regenerated from alkali/urea solution[J].Biomacromolecules,2009,10:1597-1602.
[6] Leung A C W,Hrapovic S,Lam E,et al.Characteristics and properties of carboxylated cellulose nanocrystals prepared from a novel one-step procedure[J].Small,2011,7:302-305.
[7] He M,Xu M,Zhang L N.Controllable stearic acid crystal induced high hydrophobicity on cellulose film surface[J].ACS Appl.Mater.Interfaces,2013,5:585-591.
[8] Taajamaa L,Kontturi E,Laine J,et al.Bicomponent fibre mats with adhesive ultra-hydrophobicity tailored with cellulose derivatives[J].J.Mater.Chem.,2012,22:12072-12082.
[9] Berlioz S,Molina-Boisseau S,Nishiyama Y,et al.Gas-phase surface esterification of cellulose microfibrils and whiskers[J].Biomacromolecules,2009,10:2144-2151.
[10] Wang J,Somasundaran P.Mechanisms of ethyl (hydroxyethyl) cellulose-solid interaction:influence of hydrophobic modification[J].J.Colloid Interface Sci.,2006,293:322-332.
[11] Ding B,Li C R,Hotta Y,et al.Conversion of an electrospun nanofibrous cellulose acetate mat from a super-hydrophilic to super-hydrophobic surface[J].Nanotechnology,2006,17:4332.
[12] Cheng H L,Gu B W,Duong H M,et al.Cotton aerogels and cotton-cellulose aerogels from environmental waste for oil spillage cleanup[J].Mater.Des.,2017,130:452-458.
[13] Piltonen P,Hildebrandt N C,Westerlind B,et al.Green and efficient method for preparing all-cellulose composites with NaOH/urea solvent[J].Compos.Sci.Technol.,2016,135:153-158.
[14] Dormanns J W,Schuermann J,Müssig J,et al.Solvent infusion processing of all-cellulose composite laminates using an aqueous NaOH/urea solvent system[J].Composites Part A,2016,82:130-140.
[15] Jin E S,Zhang Y,Song J L,et al.To understand the superior hydrolytic activity after polymorphic conversion from cellulose I to II from the adsorption behaviors of enzymes[J].Cellulose,2017,24:1371-1381.
[16] Cai J,Zhang L N.Rapid dissolution of cellulose in LiOH/urea and NaOH/urea aqueous solutions[J].Macromol.Biosci.,2005,5:539-548.
[17] Jin E S,Song J L,Rojas O J,et al.On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II[J].Carbohydr.Polym.,2016,143:327-335.
[2] Kyutoku H,Maeda N,Sakamoto H,et al.Effect of surface treatment of cellulose fiber (CF) on durability of PLA/CF bio-composites[J].Carbohydr.Polym.,2019,203:95-102.
[3] Xie X L,Zhong G J,Li Z M,et al.A nacre-mimetic superstructure of poly (butylene succinate) structured by using an intense shear flow and ramie fiber as a promising strategy for simultaneous reinforcement and toughening[J].J.Mater.Chem.,A,2017,5:22697-22707.
[4] Li J Y,Nawaz H,Zhang J M,et al.All-cellulose composites based on the self-reinforced effect[J].Compos.Commun.,2018,9:42-53.
[5] Qi H S,Cai J,Zhang L N,et al.Properties of films composed of cellulose nanowhiskers and a cellulose matrix regenerated from alkali/urea solution[J].Biomacromolecules,2009,10:1597-1602.
[6] Leung A C W,Hrapovic S,Lam E,et al.Characteristics and properties of carboxylated cellulose nanocrystals prepared from a novel one-step procedure[J].Small,2011,7:302-305.
[7] He M,Xu M,Zhang L N.Controllable stearic acid crystal induced high hydrophobicity on cellulose film surface[J].ACS Appl.Mater.Interfaces,2013,5:585-591.
[8] Taajamaa L,Kontturi E,Laine J,et al.Bicomponent fibre mats with adhesive ultra-hydrophobicity tailored with cellulose derivatives[J].J.Mater.Chem.,2012,22:12072-12082.
[9] Berlioz S,Molina-Boisseau S,Nishiyama Y,et al.Gas-phase surface esterification of cellulose microfibrils and whiskers[J].Biomacromolecules,2009,10:2144-2151.
[10] Wang J,Somasundaran P.Mechanisms of ethyl (hydroxyethyl) cellulose-solid interaction:influence of hydrophobic modification[J].J.Colloid Interface Sci.,2006,293:322-332.
[11] Ding B,Li C R,Hotta Y,et al.Conversion of an electrospun nanofibrous cellulose acetate mat from a super-hydrophilic to super-hydrophobic surface[J].Nanotechnology,2006,17:4332.
[12] Cheng H L,Gu B W,Duong H M,et al.Cotton aerogels and cotton-cellulose aerogels from environmental waste for oil spillage cleanup[J].Mater.Des.,2017,130:452-458.
[13] Piltonen P,Hildebrandt N C,Westerlind B,et al.Green and efficient method for preparing all-cellulose composites with NaOH/urea solvent[J].Compos.Sci.Technol.,2016,135:153-158.
[14] Dormanns J W,Schuermann J,Müssig J,et al.Solvent infusion processing of all-cellulose composite laminates using an aqueous NaOH/urea solvent system[J].Composites Part A,2016,82:130-140.
[15] Jin E S,Zhang Y,Song J L,et al.To understand the superior hydrolytic activity after polymorphic conversion from cellulose I to II from the adsorption behaviors of enzymes[J].Cellulose,2017,24:1371-1381.
[16] Cai J,Zhang L N.Rapid dissolution of cellulose in LiOH/urea and NaOH/urea aqueous solutions[J].Macromol.Biosci.,2005,5:539-548.
[17] Jin E S,Song J L,Rojas O J,et al.On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II[J].Carbohydr.Polym.,2016,143:327-335.