Microcrystalline Cellulose Composites Research Articles

Facile synthesis of Co, Fe-bimetallic MIL-88A/microcrystalline cellulose composites for efficient adsorptive and photo-Fenton degradation of RhB dye

Photo-Fenton technology is effective in treatment of dye containing effluents in water under visible light illumination. The present article reports fabrication of a considerably efficient photo-Fenton catalytic system, the Co, Fe-MIL88/MCC composite, by a mild hydrothermal method. The composite containing bimetals Co2+/Co3+ and Fe2+/Fe3+ ions with coordination environments used as activators of H2O2-assited visible light photo-Fenton degradation of RhB. The effects of initial pH, catalyst dosage and H2O2 concentration on RhB decomposition were explored. Nearly 87% of RhB molecule was removed within 100 min in the Co, Fe-MIL88/MCC/H2O2/Visible system ana maintain the recyclability rate of more than 82.2% after five successive cycles. The photoinduced •O2− and •OH plays a major role in efficient removal of RhB. The excellent catalytic performance of the composite can be credited to the proficient electrons transfer by Fe2+/Fe3+ and Co2+/Co3+ redox cycles, activation of H2O2 by photoexcited electrons to generate •OH. As well, the optimal Co, Fe-MIL88 (Co/Fe in ratio 1/2 wt%)/MCC composite exhibited good recyclability and stability.

Development and molecular dynamics simulation of green natural rubber composites with modified sisal microcrystalline cellulose

AbstractIn this study, green composites were prepared using natural rubber (NR) as the matrix and the sisal microcrystalline cellulose (MCC) as the filler. Three modifying agents oleic acid (OA), γ‐aminopropyltriethoxylsilane (KH550), and bis‐γ‐(triethoxysilylpropyl)‐tetrasulfide (Si69) were individually tested to modify the MCC to improve the interfacial compatibility of the NR and MCC. Combined with modern instrumental analysis technology and molecular dynamics simulation, the reinforcing effect and microscopic mechanism of modified MCC on NR were analyzed. The structure–activity relationship of NR and MCC composites was further revealed, and the interaction between the two components was clarified. At the same time, the reinforcing and compatibilizing effect of three kinds of modified MCC in NR matrix were also revealed. The results showed that the properties of NR/Mod‐MCC composites were better than those of NR/MCC composites, where NR/OA‐MCC presented the highest tensile strength, followed by NR/Si69‐MCC. In addition, NR/Si69‐MCC exhibited higher elongation at break and NR/KH550‐MCC exhibited higher vulcanization characteristics. Molecular model systems were constructed through molecular dynamics simulation to investigate the interactions between the three modified cellulose molecules and the NR molecules. OA‐cellulose has a better interaction with NR than KH550‐cellulose and Si69‐cellulose, The simulation results were consistent with the experimental results.

Preparation and characterization of thermoplastic starch/bamboo shoot processing by-product microcrystalline cellulose composites

Preparation and characterization of thermoplastic starch/bamboo shoot processing by-product microcrystalline cellulose composites

Lignin as a dry bonding system component in EPDM/microcrystalline cellulose composites

AbstractThis study aims at using lignin in place of resorcinol in hexamethylene‐tetramine, resorcinol and hydrated silica (HRH) bonding system for ethylene propylene diene monomer (EPDM)/microcrystalline cellulose (MCC) composites. Various percentages of lignin (0%, 50%, 75%, and 100% with respect to resorcinol weight) were used. The rheometric, mechanical, thermo‐aging, swelling, and dielectric properties of the produced composites were investigated. It was found that the introduction of 50% of lignin produced composite with superior mechanical, thermo‐aging and swelling properties. Furthermore, the dielectric properties of the composites showed a significant enhancement with 100% of resorcinol replacement with lignin.

Effect of Fiber Loading on the Chemical, Structural and Mechanical Properties of 3D Printed Polylactic Acid/Abaca Microcrystalline Cellulose Composites

In an attempt to improve the physical properties of 3D printed poly lactic acid (PLA), this study aims to develop a microcrystalline cellulose fiber and observe the effects of fiber loading on the PLA/cellulose composites to the composition, crystallinity, morphology, and tensile properties of the resulting 3D printed material. Microcrystalline cellulose (MCC) have been extracted from indigenous raw abaca fibers and used as the fiber reinforcement for the PLA matrix. Composites of 1 and 3 wt% MCC fibers with PLA were processed using the twin-screw extruder to produce filaments. The resulting composite filaments were 3D printed utilizing the fused deposition modeling technology. FTIR, XRD, digital microscopy, and mechanical testing were used in characterizing the various 3D printed PLA/MCC composite. With the incorporation of cellulose, the PLA/MCC had up to 32% increase in tensile strength and 43% increase in modulus at just 3 wt% fiber loading due to the inherent high modulus of abaca cellulose. The MCC significantly influences the chemical, structural and mechanical properties of the 3D printed PLA/MCC composites.

Experimental Analysis of the Enzymatic Degradation of Polycaprolactone: Microcrystalline Cellulose Composites and Numerical Method for the Prediction of the Degraded Geometry.

The degradation rate of polycaprolactone (PCL) is a key issue when using this material in Tissue Engineering or eco-friendly packaging sectors. Although different PCL-based composite materials have been suggested in the literature and extensively tested in terms of processability by material extrusion additive manufacturing, little attention has been paid to the influence of the fillers on the mechanical properties of the material during degradation. This work analyses the possibility of tuning the degradation rate of PCL-based filaments by the introduction of microcrystalline cellulose into the polymer matrix. The enzymatic degradation of the composite and pure PCL materials were compared in terms of mass loss, mechanical properties, morphology and infrared spectra. The results showed an increased degradation rate of the composite material due to the presence of the filler (enhanced interaction with the enzymes). Additionally, a new numerical method for the prediction of the degraded geometry was developed. The method, based on the Monte Carlo Method in an iterative process, adjusts the degradation probability according to the exposure of each discretized element to the degradation media. This probability is also amplified depending on the corresponding experimental mass loss, thus allowing a good fit to the experimental data in relatively few iterations.

Study on the properties of PLA/PBAT composite modified by nanohydroxyapatite

Poly(lactic acid) (PLA) and poly(butylene adipate-Co-terephthalate) (PBAT) show high and excellent biocompatibility, which are promising materials used in bone tissue engineering field. In this research, n-HA/PLA/PBAT/MCC composites were prepared by solution blending method. Nano hydroxyapatite (n-HA) was used as nucleation, and microcrystalline cellulose (MCC) was added to improve the degradation performance of the materials. Compared with the composite without n-HA, the crystallinity of the composites with 6% n-HA was increased by 62%. The scanning electron microscopy (SEM) and the transmission electron microscopy (TEM) showed that the n-HA was evenly dispersed in the composites when the addition ration of n-HA was lower than 6%, while obvious agglomeration of n-HA appeared at the addition ratio of 10%. The tensile test demonstrated that the tensile strength of the composites with different addition ratio transcended the needs of bone tissue engineering materials. The introduction of n-HA in obtained composites simulated the composition and structure of native bone, which suggested a potential utility and application prospect in bone tissue engineering.

Thermal- and water-induced shape memory Eucommia ulmoides rubber and microcrystalline cellulose composites

Abstract We designed a series of new thermal and water double-stimulus shape memory composites composed of natural Eucommia ulmoides rubber (EUR) and microcrystalline cellulose (MCC) and discussed their excellent properties in this manuscript. The shape memory behavior of the composites was investigated under three stimulation conditions: heat, water and heat and water. We studied the mechanism of heat-and water-triggered shape memory properties by considering the mechanical properties, water contact angle, water uptake, thermal properties and microstructure of the composites. We also proposed two schematic diagrams to explain the relationship between the internal microstructures and the macroscopic properties of the materials. Due to the excellent multi-responsive properties, these kinds of intelligent shape memory composites can potentially be applied in biomedical and special sensor field.

Evaluation of the performance of microcrystalline cellulose in retarding degradation of two epoxy resin systems

Accelerated weathering studies are necessary to determine future risks arising from the loss of durability of materials under environmental conditions (e.g. ultraviolet irradiation from the sun, moisture from rainfall, temperature cycling). The influence of different accelerated weathering conditions such as UV light and moisture on the properties of two epoxy resin systems incorporating microcrystalline cellulose (MCC) was evaluated. This study aimed to assess changes in chemical properties (FTIR), mechanical properties (tensile tests), thermal properties (TGA and DSC) and morphology (SEM) before and after accelerated weathering. The samples exposed to different accelerated weathering times (1, 2, 3, 4, and 6 months) were based on the diglycidyl ether of bisphenol A, DGEBA, or hydrogenated diglycidyl ether of bisphenol A, HDGEBA, with amine crosslinker (2,2,4-trimethyl-1,6-hexanediamine, TMDA) and 2% MCC. Incorporation of MCC improved thermal stability, reduced surface oxidation, and gave better retention of mechanical properties after accelerated weathering. Both epoxy resins and epoxy composites exhibited a reduction in the tensile strength upon accelerated weathering with the composites showing less reduction in the tensile strength after 6 months. The glass transition temperatures (Tg) before and after accelerated weathering were also measured. DGEBA-TMDA/2%MCC and HDGEBA-TMDA/2% MCC composites reduced the decrease in the Tg after accelerated weathering, compared to that of DGEBA-TMDA and HDGEBA-TMDA samples. Degradation primarily decreased the mechanical properties of the composites, with some damaged specimens showing on the surfaces of DGEBA-TMDA/2% epoxy composites and HGEBA-TMDA/2%MCC composites. Fewer morphological changes with limited voids were seen on the DGEBA epoxy interface for HDGEBA compared to DGEBA composite samples. Incorporation of 2%MCC in DGEBA-TMDA and HDGEBA-TMDA increased resistance to thermal degradation after accelerated weathering.

Preparation of Maleic Anhydride Grafted Polybutene and Its Application in Isotactic Polybutene-1/Microcrystalline Cellulose Composites.

Microcrystalline cellulose (MCC) offers great potential to improve the mechanical and crystallization properties of isotactic polybutene-1 (iPB) because of its low cost, biodegradability, renewability and excellent mechanical properties. However, the compatibility of polar MCC and non-polar iPB is poor. In this study, maleic anhydride grafted polybutene (MAPB) was prepared by the solution method and was used as a compatibilizer in the fabrication of iPB/MCC composites by using a twin screw extruder. The ultimate tensile strength, tensile modulus, flexural strength, flexural modulus of the iPB/MCC composites increased by 3.1%, 16.5%, 10.7%, 6.5%, respectively, compared with that of pure iPB. With MAPB addition, these values increased by 17.2%, 31%, 17.5% and 10%, respectively, compared with that of pure iPB. The heat-distortion temperature and thermal-decomposition temperature of all composites increased with an increased MCC content. The non-isothermal crystallization of the iPB/MCC composites shows that MCC addition can promote iPB crystallization, because the non-isothermal crystallization curve of the composites moves toward a higher temperature, especially after MAPB addition. Scanning electron micrographs indicate that the compatibility of the iPB/MCC has been enhanced significantly.

Comparison of Morphology and Mechanical Properties of Polyoxymethylene/Cellulose and Poly(Lactic Acid)/Cellulose Composites

The objective of this study is to fabricate the polyoxymethylene (POM)/microcrystalline cellulose (MCC) and poly(lactic acid) (PLA)/MCC composites, and to compare the effect of MCC on the morphology and mechanical properties of POM and PLA. The polymer composites were prepared by melt mixing in an internal mixer and molded by compression molding. The MCC concentrations were 1, 3, 5, 7, 10, 15 and 10% by weight. From scanning electron microscopy study observes the fracture surface of POM and PLA composites is much rough and the roughness increases with increasing MCC content. This observation indicates MCC induces the ductile fracture characteristic of POM and PLA. The addition of MCC can improve the impact strength of PLA composite and improve Young’s modulus of both POM and PLA composites. While the tensile strength and strain at break decrease after adding MCC. In summary, MCC can enhance the morphology and mechanical properties of PLA composites is better than POM composites.

Preparation of acylated microcrystalline cellulose using olive oil and its reinforcing effect on poly(lactic acid) films for packaging application

A novel poly(lactic acid) (PLA) based composite, reinforced by microcrystalline cellulose (MCC) was prepared. MCC was modified by esterification reaction using olive oil for improving the compatibility with PLA matrix. The acylated microcrystalline cellulose (AMCC) exhibited reduced polarity in comparison to unmodified MCC. AMCC/ PLA composite films were prepared using solvent casting technique. The effects of the MCC surface modification on morphological, mechanical, physical, thermal, biodegradability and barrier properties of the PLA based MCC composites were studied. FTIR analysis confirmed acylation reaction of MCC. Scanning electron microscopy analysis exhibited a uniform distribution of AMCC in PLA matrix. Barrier properties of AMCC based composites were improved as compared to MCC based composites. The tensile strength and tensile modulus of composite films (at 2 wt.% AMCC) were improved about 13% and 35% as much as those of the pure PLA films, respectively. These biodegradable composite films can be a sustainable utilization of olive oil and microcrystalline cellulose in the food packaging application.

Impact of Bis-(3-triethoxysilylpropyl)tetrasulphide on the properties of PMMA/Cellulose composite

Poly(methyl methacrylate) (PMMA)-microcrystalline cellulose composites with improved interfacial interaction were prepared by solution casting method using Bis-(3-triethoxysilylpropyl) tetrasulphide (Si69) as coupling agent. The incorporation of microcrystalline cellulose into PMMA enhanced the mechanical as well as thermal properties over that of base polymer but not remarkably. So in the current study Bis-(3-triethoxysilylpropyl) tetrasulphide (Si69) is used as a coupling agent to improve PMMA-Cellulose adhesion. The composites were characterized using FTIR, 13C NMR, UV–Vis, 29Si NMR, XRD and SEM analysis. The results indicated that Si69 formed chemical bonds with both PMMA and cellulose. The effect of Si69 on the physical and mechanical properties of PMMA/Cellulose composite was investigated. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies showed that the degradation temperature and glass transition temperature of PMMA shifted to higher temperature. The addition of silane coupling agent in to the PMMA/Cellulose improved the mechanical properties. The impact strength increased up to 72%, flexural strength by 37%. The composite exhibited 49% higher tensile strength and 50% storage modulus than pristine PMMA. The addition of cellulose to PMMA increased the dielectric constant and attained an AC conductivity of 1.4*10−4 S/m. The result proved that Si69 is compactable to both PMMA and cellulose and can be used as an effective coupling agent for PMMA/Cellulose system.

Barrier, Mechanical and Thermal of Polyvinyl Alchol/Microcrystalline Cellouse Composites in Packaging Application

In this study Polyvinyl alcohol (PVA) and (3, 5, 10%)wt microcrystalline cellulose (MCC) were prepared using a solution-casting method. The films that were produced characterized with Fourier Transform Infrared Spectrometry, Differential Scanning Calorimetric, Tensile test, and Barrier properties. The results from FTIR shows that PVA and MCC were considered miscible and compatible owing to hydrogen bonding interaction. Results for Thermal analyses increased in the glass transition temperature (T_g) thermal stability of polyvinyl alchol. Tensile strength of the films were increased with the increased loading of MCC to a composites films. Water vapor permeability of the MCC composites was increased with increasing with content of MCC in the films but oxygen transmission rate was decreased.

Comparison of polyolefin biocomposites prepared with waste cardboard, microcrystalline cellulose, and cellulose nanocrystals via solid-state shear pulverization

As a significant part of municipal solid waste (MSW), waste cardboard (CB) is a sustainable, inexpensive, and rich source of cellulose. Previous studies of polyolefin/CB composites have reported modest enhancement to major reduction in modulus and major reduction in elongation at break values relative to neat polymer. Here, green hybrids of low density polyethylene (LDPE) and polypropylene (PP) with 5–25 wt% CB are made by solid-state shear pulverization (SSSP), which achieves both size reduction of 2–3 cm sized CB pieces to the micron level and dispersion in polymer. The properties obtained with CB incorporation in LDPE and PP are compared and contrasted with those obtained with incorporation of microcrystalline cellulose (MCC) and cellulose nanocrystal (CNC). Polyolefin composites with CB made by SSSP exhibit major enhancement in Young's modulus (63% and 71% increases for 10 wt% CB in LDPE and 15 wt% CB in PP, respectively). The PP/CB composites exhibit a broad range of property enhancements relative to neat PP, including a nearly 50% nucleating efficiency, as much as an 8% increase in PP crystallinity, and a factor of ∼3 decrease in crystallization half-time. Well-dispersed CB particles improve LDPE and PP thermo-oxidative stability as shown by thermogravimetric analysis (∼5–20 °C increase in 20% mass loss temperature in air with 15–20 wt% CB addition) and isothermal shear flow rheology. Similarly, post-SSSP high-temperature, long-time melt mixing results in no apparent degradation of LDPE/CB and MCC composites whereas LDPE/CNC composites show major degradation. When incorporated into polyolefin composites, low cost, cellulose-rich MSW can often produce reinforcement similar to glass fibers and thus has potential as filler for structural composite applications.

Poly 2-ethyl-2-oxazoline/microcrystalline cellulose composites for cultural heritage conservation: Mechanical characterization in dry and wet state and application as lining adhesives of canvas

The aim of this work is the investigation of the stabilizing effect of microcrystalline cellulose powder (MCC) on the mechanical performance of two commercial thermoplastic resins (Aquazol® 200 and Aquazol® 500) used as adhesives in the conservation of artworks. The two polymers, having different molecular weights, were melt-compounded and compression molded with various amounts of MCC (5–30wt%). The mechanical response of the microcomposites under dry and wet (equilibrium at 23°C and a R.H. 55%) conditions, was investigated. DMTA analysis showed an increase of the dynamic moduli and the glass transition temperature with the microfiller content more pronounced for conditioned samples over the dried ones, and a concurrent decrease of the thermal expansion coefficient. Creep tests showed that MCC caused an improvement of the creep stability (i.e. a reduction of the creep compliance) for both dried and conditioned samples. For wet samples, the simultaneous enhancement of the elastic modulus and the stress at break limited the embrittling effect detected for dried composites. These materials were applied as lining adhesive for oil paintings between two kinds of canvas an English linen and a woven polyester under environmental conditions at temperature of 23°C and a relative humidity of 55%. Single-lap shear tests both in quasi-static and creep conditions confirmed the improvement of the dimensional stability provided by MCC with a reduction of the joint displacement and an increase of the adhesive strength as the filler content increases. Additionally, post-fracture optical microscope observations of the cross-sections of the adhesive area proved how MCC introduction did not change the fracture behavior of the neat adhesives.

Innovative microcrystalline cellulose composites as lining adhesives for canvas

Thin adhesive composite films were prepared by melt‐compounding and compression molding of a thermoplastic resin (Paraloid® B72) widely used for art protection and restoration with a microcrystalline cellulose powder (MCC). To simulate an oil painting restoration work, MCC‐based composites were applied as lining adhesives on two kinds of canvases (English linen and woven polyester). Interestingly, single–lap shear tests both in quasi‐static and creep conditions showed a remarkable stabilizing effect provided by MCC addition. Post‐mortem microstructural analysis of the overlap adhesive area proved how MCC introduction did not change the fracture behavior of the bonded joints. The visual assessment of transparency and color measurements evidenced a chromatic variation of MCC‐based films with a filler amount of 30 wt%, while, UV‐vis analysis showed a decrease of relative transmittance in proportion to the MCC content. Additionally, rheological tests highlighted a viscosity increase for Paraloid B72 in both dry and wet conditions (T = 23°C and RH = of 55%) as the MCC content increases. POLYM. ENG. SCI., 55:1349–1354, 2015. © 2015 Society of Plastics Engineers

Polyamide 6–Cellulose Composites: Effect of Cellulose Composition on Melt Rheology and Crystallization Behavior

Melt rheology and crystallization behavior of polyamide 6 (PA 6) and microcrystalline cellulose (MCC) composites were systematically studied in this research. The incorporation of MCC into the PA 6 matrix resulted in higher complex viscosities (|η*|), storage modulus (G′), and shear viscosities than those of neat PA 6, especially at low frequencies. The orientation of rigid molecular chains in the composites introduced by the addition of MCC induced a strong shear thinning behavior with an increase in MCC loading. The non‐isothermal crystallization kinetics of PA 6 and MCC composites were investigated by differential scanning calorimetry. The Avrami and Tobin model were applied to describe the process of non‐isothermal crystallization and to determine the crystallization parameters of the composites. Analysis of the crystallization kinetics indicated that the Avrami (na) and Tobin exponent (nt) was altered by the MCC. It was also found that the Avrami and Tobin equations fit the empirical data well. POLYM. ENG. SCI., 54:739–746, 2014. © 2013 Society of Plastics Engineers

Polypropylene–microcrystalline cellulose composites with enhanced compatibility and properties

Polypropylene (PP)–microcrystalline cellulose (MCC) composites were prepared containing Poly(propylene- graft-maleic anhydride) (PP- g-MA) and MCC treated with silicone oil, stearic acid or alkyltitanate coupling agent to promote matrix–filler dispersion and compatability. Infrared spectroscopy confirmed surface treatment. MCC content and PP- g-MA increased PP thermal stability and crystallisation temperature ( T c), though reduced crystallinity due to cellulose II crystals. Tensile stress–strain analysis revealed increased modulus with MCC content, PP- g-MA, alkyltitanate and stearic acid. MCC and PP- g-MA reduced creep deformation and increased permanent strain. Storage modulus, loss modulus and glass transition temperature increased with MCC concentration due to effective interaction between PP and MCC.

Mechanical properties of biodegradable composites from poly lactic acid (PLA) and microcrystalline cellulose (MCC)

AbstractBiodegradable composites were prepared using microcrystalline cellulose (MCC) as the reinforcement and polylactic acid (PLA) as a matrix. PLA is polyester of lactic acid and MCC is cellulose derived from high quality wood pulp by acid hydrolysis to remove the amorphous regions. The composites were prepared with different MCC contents, up to 25 wt %, and wood flour (WF) and wood pulp (WP) were used as reference materials. Generally, the MCC/PLA composites showed lower mechanical properties compared to the reference materials. The dynamic mechanical thermal analysis (DMTA) showed that the storage modulus was increased with the addition of MCC. The X‐ray diffraction (XRD) studies on the materials showed that the composites were less crystalline than the pure components. However, the scanning electron microscopy (SEM) study of materials showed that the MCC was remaining as aggregates of crystalline cellulose fibrils, which explains the poor mechanical properties. Furthermore, the fracture surfaces of MCC composites were indicative of poor adhesion between MCC and the PLA matrix. Biodegradation studies in compost soil at 58°C showed that WF composites have better biodegradability compared to WP and MCC composites. The composite performances are expected to improve by separation of the cellulose aggregates to microfibrils and with improved adhesion. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2014–2025, 2005