Characterization and Selection of Microcrystalline Cellulose from Oil Palm Empty Fruit Bunches for Strengthening Hydrogel Films

Microcrystalline cellulose(MCC)is one of the cellulose derivatives produced as a result of the depolymerization of a part of cellulose to achieve high crystallinity.When implemented in other polymers,high crystallinity correlates with greater strength and stiffnes,but it can reduce the water-holding capacity.The acid concentration and hydrolysis time will affect the acquisition of crystallinity and water absorption capacity,both of which have significance as properties of hydrogel filler.The study aimed to evaluate the properties and select the MCC generated from varying the proportion of hydrochloric acid(HCl)and the appropriate hydrolysis time as a filler for film hydrogel.MCC was produced by hydrolyzing cellulose of oil palm empty fruit bunches(OPEFB)with the HCl solution at varied concentrations and periods.The results show that the longer hydrolysis times and higher HCl concentrations increase crystallinity and density while lowering yield and water absorption.The extensive acid hydrolysis reduces the amorphous area significantly,allowing the depolymerization to occur and extend the crystalline area.The morphological properties of the MCC,which are smaller but compact,indicate the presence of disintegrating and diminishing structures.A 2.5 N HCl concentration and a 45-min hydrolysis time succeed in sufficient crystallinity as well as maintaining good water absorption capacity.The treatment produced MCC with absorption capacity of 4.03±0.26 g/g,swelling capacity of 5.03±0.26 g/g,loss on drying of 1.44%±0.36,bulk and tapped density of 0.27±0.031 g/cm^(3) and 0.3±0.006 g/cm^(3),respectively,with a crystallinity index of 88.89%±4.76 and a crystallite size of 4.23±0.70 nm.The MCC generated could potentially be utilized as a hydrogel film filler,since a given proportion will be able to maintain the strength of the hydrogel,not readily dissolve but absorb water significantly.

Effect of Water Content on Crystalline Structure of Ionic Liquids Mixture Pretreated Microcrystalline Cellulose (MCC)

Microcrystalline cellulose (MCC) was pretreated by using ionic liquids (ILs)-water mixtures solvent with solid acid catalysts. Different amount of water was considerate as the main variable. The peak shift of pretreated sample was determined by FT-IR related to the water content. The XRD was applied to characterize the change in MCC crystalline structure. Thermal decomposition technique was applied to investigate the thermal stability of pretreated MCC. The result indicated that three state of samples were occurred in pretreated MCC sample which was related the amount of water in ILs mixture system. XRD result suggested that the raw sample was distorted and transformed into a less ordered intermediate structure and the smaller crystallite size in lump state sample was obtained which could lead to lower thermal stability. This study revealed the physical chemicals properties, characteristic of molecular structures in MCC using ILs-water mixtures.

Biocomposite Films of Polylactic Acid Reinforced with Microcrystalline Cellulose from Pineapple Leaf Fibers

Poly(lactic acid)(PLA)composite films reinforced with microcrystalline cellulose(MCC)extracted from pineapple leaf fibers(PALF)were prepared by a solution casting procedure.In an attempt to improve the interaction between PLA and cellulose,two approaches were adopted;first,poly(ethylene glycol)(PEG)was used as a surfactant,and second,the cellulosic fibers were pre-treated using tert-butanol(TBA).Lignocellulosic and cellulosic substrates were characterized using Fourier transform infrared(FTIR),wide-angle X-ray scattering(WAXS),and thermogravimetrical analysis(TGA).MCC from PALF showed good thermal stability,left few residues after decomposing,and exhibited high crystallinity index.Mechanical,thermal and thermomechanical properties of the PLA composites were also evaluated.Multiple PLA endotherms were observed in composites with TBA-treated MCC due to crystal nucleation effects.The ultimate tensile strain values for all composites were lower than that of the pristine PLA.However,4 wt.%MCC content provided balanced engineering properties in terms of static and dynamic tensile properties.

Rapid and Efficient Adsorption Removal of Reactive Blue 4 from Aqueous Solution by Cross-Linked Microcrystalline Cellulose–Epichlorohydrin Polymers: Isothermal, Kinetic, and Thermodynamic Study

In this study, we modified microcrystalline cellulose by cross-linking it with epichlorohydrin to obtain a rapid and efficient adsorbent for the removal of Reactive Blue 4 dye from aqueous solution. Evidences of the cross-linking of the microcrystalline cellulose were obtained by Fourier transform infrared spectroscopy, X-ray diff raction, Brunauer–Emmett–Teller analysis, thermogravimetric analysis, and scanning electron microscopy. We investigated the eff ects of adsorbent dosage, p H, initial dye concentration, temperature, and contact time on the dye adsorption capacity. The results showed that the adsorption equilibrium time was just 20 min and the maximum adsorption capacity was 69.79 mg/g. The adsorption isotherm data fitted the Langmuir isotherm model well, and the adsorption kinetics data followed the pseudo-second-order kinetic model. The results of the thermodynamic analysis suggest that the adsorption process was spontaneous and exothermic. Recyclability experiments demonstrated the good reusability of this adsorbent. Electrostatic interaction was found to dominate the adsorption process.

Preparation of Highly Crystalline Microcrystalline Cellulose by Hydrolysis of Cellulose with Phosphotungstic Acid

Phosphotungstic acid(H_3PW_(12)O_(40), HPW), a kind of solid acid, is widely used for hydrolyzing cellulose to prepare microcrystalline cellulose(MCC). MCC is usually used in food, synthetic leather, chemical and pharmaceutical industries. The use of response surface methodology(RSM)can help avoid the random error caused by single factor experimental design,reduce test times and cost, and improve quality. The RSM was used in this study to determine the following optimal process conditions: H^+ molar quantity, 31 mmol/L; reaction temperature, 93℃; reaction time, 2 h; and solid to liquid ratio, 1∶38. Under these conditions, the crystallinity of MCC was77.4%. Thus, the use of RSM allows the preparation of MCC with higher performance and increased crystallinity.

Obtaining and Characterization of Biodegradable Composites Reinforced with Microcrystalline Cellulose Fillers

In recent years, there has been a growing discussion about the problems related to the massive use of many synthetic plastic materials, which inevitably leads to an increase in environmental pollution caused by the inappropriate disposal of these materials. In this sense, biodegradable materials have been a subject of great interest, as they are a real alternative to replace these materials and tackle this issue. In this work, fully biodegradable composites were prepared by solution casting method. Microcrystalline cellulose (MCC) and treated microcrystalline cellulose (TMCC) were separately incorporated into biodegradable PLA and PHB matrices at ratios of 3, 5 and 7 wt% and the properties of the obtained biocomposites were evaluated by TGA, DSC, XRD and TD-NMR. From thermal analyses, it was seen that TMCC resulted in better thermal stability and 3 wt% of filler, in general, promoted a more pronounced thermal improvement. Furthermore Tg, Tc and Tm remained practically unchanged after MCC and TMCC addition. From XRD it was seen that the cellulose fillers influence in different ways the matrices, promoting increase or decrease in the degree of crystallinity. Finally, the results obtained by TD-NMR showed a decrease in the T1H values for all prepared biocomposites, indicating a good dispersion of the cellulose fillers in the matrices and pointed that the systems containing 3 wt% of cellulose fillers were the most homogeneous formulations.

Preparation of highly stable diclofenac potassium pellet with microcrystalline cellulose by extrusionespheronization

The main purpose of this study is to prepare highly stable diclofenac potassium(DP)pellet with microcrystalline cellulose(MCC)by extrusionespheronization.Using MCC,DP pellets were prepared and the stability was investigated.Related compounds of DP pellets were analyzed by High Pressure Liquid Chromatography(HPLC).After stability test of 60℃/75%RH for 10 d,the values of two main related compounds were 0.94%and 2.17%,respectively.Compatibility tests show that instability of DP was mainly caused by MCC.To improve the stability of DP in presence of MCC,different kinds of stabilizers were investigated.Upon addition of 1.5%(w/w)sodium hydroxide,the primary related compound of pellets was reduced to be 0.159%after stability test of 60℃/75%RH for 50 d.This study demonstrated that MCC induced decomposition of DP upon exposure to moisture could be prohibited by addition of sodium hydroxide.The mechanisms were discussed and residual hydroxyl free radicals in excipients were responsible for decomposition of DP.Finally,this formulation of DP is highly stable with sustained-release behavior.

Kevlar fabric reinforced polybenzoxazine composites filled with silane treated microcrystalline cellulose in the interlayers:The next generation of multi-layered armor panels

The design of astonishing combinations of benzoxazine resins with various fillers is nowadays of great interest for high quality products,especially in ballistic armors.The objective of this study is to investigate a new hybrid material prepared as multi-layered composite plate by hand lay-up technique.Different composites were manufactured from Kevlar fabrics reinforced polybenzoxazine,which was filled with silane treated microcrystalline cellulose(MCC Si)at various amounts in the interlayers.The developed materials were tested for their flexural,dynamic mechanical and ballistic performance.The aim was to highlight the effect of adding different amounts of MCC Si on the behavior of the different plates.Compared to the baseline,the dynamic mechanical and bending tests revealed an obvious decrease of the glass transition of 21℃and a notable increase in storage modulus and flexural strength of about 180%and17%,respectively,upon adding 1%MMC Si as filler.Similarly,the ballistic test exhibited an enhancement in kinetic energy absorption for which the composite supplemented with 1%MCC Si had the maximal energy absorption of 166.60 J.These results indicated that the developed panels,with interesting mechanical and ballistic features,are suitable to be employed as raw materials to produce body armor.

Investigation of Agave cantala-based composite fibers as prosthetic socket materials accounting for a variety of alkali and microcrystalline cellulose treatments

This study was aimed to determine the mechanical strength of composites made from Agave cantala with an unsaturated polyester matrix and microcrystalline cellulose.Cantala fiber(CF)was treated with 6%Na OH with immersion times of 0 h(UF),3 h(AK3),6 h(AK6),9 h(AK9),and12 h(AK12).Thermogravimetric analysis(TGA)analysis shows that treated CF has higher thermal stability than CF without treatment.Cantala fiber was tested by X-ray diffraction.After alkali treatment with a 6-h soaking,it had a crystallinity index of 73.65%.Scanning electron microscopy(SEM)showed that the fibers were cleaner after alkali treatment because hemicellulose,wax,and other impurities were removed.Examination of the contact angle and surface energy showed that treated CF has smaller contact angles and greater surface energy.

Synthesis of Microcrystalline Cellulose—Polyvinyl Alcohol Stabilized Polyvinyl Acetate Emulsion

Polyvinyl alcohol (PVA) colloid stabilized Polyvinyl acetate (PVAc) based wood adhesive has poor performance in highly humid conditions. Currently, the addition of natural fillers in the wood adhesive is one of the most effective ways to enhance the performance of PVAc wood adhesive in highly moist conditions. Microcrystalline cellulose (MCC) are strong renewable, bio-based material and has great potential in a reinforcement of the polymeric matrix. Hence, the present work investigates the applicability of microcrystalline cellulose incorporated 3% and 5% in situ emulsion polymerization PVAc wood adhesives. Effect on physical, thermal and mechanical properties was studied by viscosity, pH, contact angle measurement, differential scanning calorimetry (DSC) and pencil hardness test of films. Emulsions with different proportions of MCC were prepared and the shear strength of the applied adhesive on wood was measured. The viscosity of the adhesives was increased by increasing the concentration of MCC. The mechanical properties like tensile strength of adhesives with MCC were measured by universal tensile machine (UTM). Thermal stability was studied by differential scanning calorimetry (DSC). The tensile shear strength demonstrates that MCC can improve bonding strength as compared to PVAc Homo based adhesive in the wet condition which was validated through a contact angle study. The hardness of PVAc films were also changed positively by the addition of MCC. Here, we studied the effect of the addition of different concentrations of MCC materials in situ polymerization of PVAc on their performance properties.

Adsorption behavior of free fatty acids and micro-components in rapeseed oil on alkaline microcrystalline cellulose

Alkaline microcrystalline cellulose (AMC) was used as adsorption agent in deacidification in this paper. Changes of isothermal adsorption of free fatty acids (FFA) and micro-components (α-tocopherol and β-sitosterol) in rapeseed oil on AMC were investigated. The results showed that difference in initial micro-component contents would not change adsorption characteristics of AMC to FFA. Adsorption characteristics were always as the following: Langmuir equation was more suitable to static adsorption process of AMC to FFA than Freundlich equation; moderate temperature (30-40oC) was advantageous to adsorption; adsorption was a preferential one. The highest retention rate of α-tocopherol and β-sitosterol during absorptive deacidification by AMC were 99.5% and 91.5% respectively. Therefore, AMC was suitable for adsorption deacidification application of rapeseed oil.

Rapid conversion of cellulose to 5-hydroxymethylfurfural using single and combined metal chloride catalysts in ionic liquid

Direct conversion of cellulose into 5-hydroxymethylfurfural(HMF) was performed by using single or combined metal chloride catalysts in 1-ethyl-3-methylimidazolium chloride(Cl) ionic liquid.Our study demonstrated formation of 2-furyl hydroxymethyl ketone(FHMK),and furfural(FF) simultaneously with the formation of HMF.Various reaction parameters were addressed to optimize yields of furan derivatives produced from cellulose by varying reaction temperature,time,and the type of metal chloride catalyst.Catalytic reaction by using FeCl3 resulted in 59.9% total yield of furan derivatives(HMF,FHMK,and FF) from cellulose.CrCl3 was the most effective catalyst for selective conversion of cellulose into HMF(35.6%) with less concentrations of FHMK,and FF.Improving the yields of furans produced from cellulose could be achieved via reactions catalyzed by different combinations of two metal chlorides.Further optimization was carried out to produce total furans yield 75.9% by using FeCl3/CuCl2 combination.CrCl3/CuCl2 was the most selective combination to convert cellulose into HMF(39.9%) with total yield(63.8%) of furans produced from the reaction.The temperature and time of the catalytic reaction played an important role in cellulose conversion,and the yields of products.Increasing the reaction temperature could enhance the cellulose conversion and HMF yield for short reaction time intervals(5~20 min).

Fully Bio-Based Composites of Poly(Lactic Acid)Reinforced with Cellulose-Graft-Poly-(ε-Caprolactone)Copolymers

Due to the increasing demand for modified polylactide(PLA)meeting“double green”criteria,the research on sustainable plasticizers for PLA has attracted broad attentions.This study reported an open-ring polymerization method to fabricate cellulose(MCC)-g-PCL(poly(ε-caprolactone))copolymers with a fully sustainable and biodegradable component.MCC-g-PCL copolymers were synthesized,characterized,and used as green plasticizers for the PLA toughening.The results indicated that the MCC-g-PCL derivatives play an important role in the compatibility,crystallization,and toughening of the PLA/MCC-g-PCL composites.The mechanical properties of the fully bio-based PLA/MCC-g-PCL composites were optimized by adding 15 wt%MCC-g-PCL,that is,the elongation at break was 22.6%(~376%higher than that of neat PLA),the tensile strength was 47.3 MPa(comparable to that of neat PLA),and the impact strength was 26 J/m(~130%higher than that of neat PLA).DSC results indicated that MCC-g-PCL reduced the Tg of the PLA blend.When the addition amount was 15 wt%,the Tg of the blend was 58.4°C.Compared with MCC,MCC-g-PCL polyester plasticizer has better thermal stability,T5%(°C)can still be maintained above 300°C.The rheological results showed that MCC-g-PCL acted as a plasticizer,the introduction of PCL flexible chain increased the mobility of PLA molecular chain,and decreased the complex viscosity,storage modulus and loss modulus of PLA blends.The MCC-g-PCL derivatives,as a new green plastic additive,have shown an interesting prospect to prepare fully bio-based composites.

MCC颗粒浓度及油相比例对MCC-猪油Pickering乳液制备效果的影响

为探讨微晶纤维素(microcrystalline cellulose,MCC)-猪油Pickering乳液的制备方法,分析乳化液组成对乳化效果的影响规律,以水相中MCC颗粒浓度和油相比例为变动因素,测定乳液的外观结构、乳析指数、微观结构、粒径、Zeta电位以及乳液流变特性等指标,并分析变化情况。结果表明,油相比例为50%,MCC颗粒浓度为0.4%~1.0%时,随着颗粒浓度的增加,乳液液滴粒径逐渐减小,乳析指数、Zeta电位绝对值、乳液的黏度及储能模量(G')与损耗模量(G″)逐渐增大,乳液稳定性逐渐增加。MCC颗粒浓度为1.0%,油相比例为30%~60%时,随着油相比例的增加,乳液的液滴粒径及乳析指数逐渐增加,Zeta电位绝对值呈先增大后减小趋势,乳液的黏度及储能模量(G')与损耗模量(G″)逐渐增大。因此,MCC颗粒浓度为1.0%、油相比例为50%~60%时能制备出稳定的乳化液。

Optimization of Micro Crystalline Cellulose Production from Corn Cob for Pharmaceutical Industry Investment

MCC （micro crystalline cellulose） is a very important product in pharmaceuticals, foods, cosmetics and other industries. MCC can be made from any natural cellulose materials that have high content of cellulose ranging from pure cellulose, commercial grade cellulose to lignocellulosic materials. In this work, Beeswing （-20 L） and Chaff （5/8） which are the parts of corn cobs were used as raw materials to produce MCC via alkaline degradation, bleaching and hydrolysis. The optimum conditions of alkaline degradation, bleaching and hydrolysis were studied. MCC samples that prepared from -20 L and 5/8 were characterized through XRD （X-ray diffraction）, SEM （scanning electron microscopy） and compared with the commercial MCC （Avicel PH 101）. The results show that the degree of crystallinity of alkaline degradation, bleaching and hydrolysis obtained at 10% of NaOH 95 ~C for 2 h, NaCIO21.5 g 10% of acetic acid 0.5 mL 70 ~C for 2 h, 2 N of HC1, 105 ~C for 1 h showed maximum values which are 77.07%, 75.07% and 86.84%, respectively. The degree of crystallinity and the morphology of prepared MCC correspond to that of Avicel PH 101 industrial investment has been studied, the benefits of micro crystalline cellulose production （MCC） is 3,447 baht/kg. The investment of the plant is 7,263,514 baht and the breakeven point is around 6 years.

Injection molding of highly filled microcrystalline cellulose/polycaprolactone composites with the aid of reversible Diels-Alder reaction

To tackle the challenge of producing highly filled polymer composites using the traditional injection molding technique,which is characterized by the fairly high melt viscosity that makes mold filling difficult,the authors propose a solution based on dynamic covalent chemistry.As demonstrated by the proof-of-concept experiments,the 4-arm starshaped polycaprolactone(PCL)oligomers and microcrystalline cel-lulose(MCC)are crosslinked by the reversible Diels-Alder(DA)bonds.The flowability of the compounds greatly decreases due to the dissociation of the intercomponent DA bonds at the retro-reaction tempera-ture,and the networked architecture is reconstructed during cooling as a result of the forward DA reaction.Consequently,the high-loading MCC fillers are well distributed in the matrix and covalently bonded to the nearby PCL,forming a striking contrast to the control in which linear PCL acts as the matrix.The DA bonds crosslinked biodegradable PCL composites exhibit decent mechanical strength(20.7 MPa)even at the MCC fraction of 65 wt%,which is superior to those(5-12.2 MPa)of the highly filled PCL composites(with filler contents of 50-63.8 wt%)reported so far.The proposed approach has sufficient expansibility for the fabrication of the highly filled polymer composites constructed by other types of matrix and fillers.

Effect of various aromatic compounds with different functional groups on enzymatic hydrolysis of microcrystalline cellulose and alkaline pretreated wheat straw

Low molecular aromatic compounds are detrimental to the enzymatic hydrolysis of lignocellu-lose.However,the specific role of their functional groups remains unclear.Here,a series of nine aromatic compounds as additives were tested to understand their effect on the hydrolysis yield of microcrystalline cellulose(MCC)and alkaline pretreated wheat straw.Based on the results,the inhibition of aldehyde groups on MCC was greater than that of carboxyl groups,whereas for the alkaline pretreated wheat straw case,the inhibitory effect of aldehyde groups was lower than that of carboxyl groups.Increased methoxyl groups of aromatic compounds reduced the inhibitory ef-fect on enzymatic hydrolysis of both substrates.Stronger inhibition of aromatic compounds on MCC hydrolysis was detected in comparison with the alkaline pretreated wheat straw,indicating that the substrate lignin can offset the inhibition to a certain extent.Among all aromatic com-pounds,syringaldehyde with one aldehyde group and two methoxyl groups improved the glucan conversion of the alkaline pretreated wheat straw.

离子液体中采用AGET ATRP法制备MCC-g-PGMA

在氯化1-烯丙基-3-甲基咪唑([AMIM]Cl)离子液体中,采用AGET ATRP技术,以VC为还原剂、Cu Br2/乙二胺为催化体系,成功制备了微晶纤维素接枝聚甲基丙烯酸缩水甘油酯(MCC-g-PGMA)分子。研究表明:[AMIM]Cl对微晶纤维素有较好的溶解性,最佳反应条件为GMA/乙二胺/Cu Br2/VC摩尔比为100:4:1:1,反应温度25℃,反应时间4 h,接枝效率可达54.56%,分子量分布较窄为1.48。通过FT-IR、TEM和SEM测试表明:成功合成了MCC-g-PGMA接枝共聚物分子,PGMA接枝微晶纤维素后表面形态变得粗糙,接枝共聚物在丙酮溶液中可自组装成150~200 nm的球形结构,在药物载体领域具有良好的应用潜能。

离子液体中ATRP法合成MCC-g-PGMA分子及其组装研究

在氯化1-烯丙基-3-甲基咪唑([AMIM]Cl)离子液体中溶解天然纤维素,采用ATRP技术合成了微晶纤维素接枝聚甲基丙烯酸缩水甘油酯(MCC-g-PGMA)分子。研究表明:[AMIM]Cl对微晶纤维素有较好的溶解性。最佳ATRP接枝聚合反应条件如下:n(GMA)∶n(乙二胺)∶n(CuBr)为100∶4∶1,反应温度为25℃,反应时间为4.0h,接枝率可达50%以上,分子质量分布较窄。FT-IR和SEM测试表明:在微晶纤维素上接枝了PGMA,共聚物分子PGMA接枝到MCC后,改变了其表面形态。TEM观察发现MCC-g-PGMA在不同溶剂中可组装成不同形态,在药物载体方面具有明显的应用前景。

MCC/MOF-5/RhB三元纳米复合材料的制备及其荧光性能

采用原位生长法在微晶纤维素(MCC)表面沉积金属有机骨架化合物(MOF-5),通过改变有机配体与金属离子的比例,调控MOF-5尺寸,然后采用溶剂扩散法将荧光染料负载到MOF-5和纤维素的复合物上,制备出具有荧光发光性质的三元纳米复合材料.通过FTIR、TGA、XRD、SEM、UV、PL表征复合材料组分的相互作用方式、形貌尺寸、MOF-5在纤维素上的聚集行为及荧光发光能力等.结果表明:通过调控有机配体和金属离子比例可实现MOF-5尺寸的控制,当有机配体与金属离子配比为10∶1时,尺寸为纳米级别,约为20nm左右;当RhB浓度位于10^(-2)～10^(-4) mol/L时,随着染料浓度的递减,复合材料的发光强度依次增大.