Influence Of Methylcellulose Research Articles

Soy Protein Isolate Gel Subjected to Freezing Treatment: Influence of Methylcellulose and Sodium Hexametaphosphate on Gel Stability, Texture and Structure.

Freezing affects texture and induces the loss of gel quality. This study investigated the effects of methylcellulose (MC) (0.2%, 0.4%, 0.6%) and sodium hexametaphosphate (SHMP) (0.15%, 0.3%) on the gel textural and structural properties of SPI gels before and after freezing, and explores the synergistic enhancement of gel texture and the underlying mechanisms resulting from the simultaneous addition of SHMP and MC to SPI gels. It was revealed that MC improved the strength of SPI gels through its thickening properties, but it could not inhibit the reduction of SPI gels after freezing. The 0.4% MC-SPI gel exhibited the best gel strength (193.2 ± 2.4 g). SHMP inhibited gel reduction during freezing through hydrogen bonding and ionic interactions; it enhanced the freezing stability of SPI gels. The addition of 0.15% SHMP made the water-holding capacity in SPI gels reach the highest score after freezing (58.2 ± 0.32%). The synergistic effect of MC and SHMP could improve the strength and the freezing stability of SPI gels. MC facilitated the release of ionizable groups within SPI, causing negatively charged SHMP groups to aggregate on the SPI and inhibit the freezing aggregation of proteins. These results provide a strong basis for the improvement of cryogenic soy protein gel performance by SHMP and MC.

Experimental Study on Influence of Methylcellulose on Tensile and Flexural Strength of Normal Strength Ordinary Portland Cement Concrete

Current study explores the possibility of improvement in various categories of concrete’s strengths (including tensile strength, flexural strength etc.) by using methylcellulose as an additive. The effect of methylcellulose on concrete’s compressive strength has also been investigated experimentally. Concrete samples were casted with several methylcellulose to binder ratios varying from 0.002 to 0.01 by weight of cement. Several tests were performed on concrete specimens including concrete cylinder and cube compression tests, split cylinder tests and modulus of rupture tests. Results showed that addition of methylcellulose increased the tensile strength of concrete. Addition of 0.2% of methylcellulose increased the tensile strength of concrete by 16%. This increase in tensile strength reached up to 73% of the control sample on addition of 1% methylcellulose. It was observed that the effect of methylcellulose on compressive strength of concrete depends upon the type of samples being tested (cube or cylinder). The compressive strength of concrete cylinders showed a plateau behavior with peak at 0.4% methylcellulose content with an increase of 18.7%. Effect of methylcellulose on concrete cylinder strength becomes insignificant beyond 0.6%. It was observed that addition of methylcellulose reduces the modulus of rupture values. The reduction in MOR was only 3% at 0.2% methylcellulose content but it grew to 30% at 1% methylcellulose content. The research presents an effective way of increasing tensile strength of concrete but without significant effect on concrete’s compressive strength and modulus of rupture values. These findings can be used to determine optimum content of methylcellulose to achieve desired performance from concrete depending upon the intended use.

Influence of methylcellulose on the impermeability properties of carbon nanotube-based cement pastes at different water-to-cement ratios

The notable mechanical properties of multiwalled carbon nanotubes (MWCNTs) make them a potential reinforcement for cementitious composites. However, the MWCNTs in fresh ordinary Portland cement (OPC) pastes have been reported to agglomerate easily and influences their ability to act as reinforcements, thereby creating a technical barrier for the application of MWCNTs in cement and concretes. In this study, methylcellulose (MC) was selected as an additive to increase the viscosity of the cement-based materials. The effects and mechanisms of the MC on the transport properties and pore structures of the MWCNT-based cementitious composites at different water-to-cement (w/c) ratios were studied. Instruments developed in the laboratory were applied to measure two transport properties: water sorptivity and gas permeability. Furthermore, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) was used to further illustrate the pore structure effects from the reinforcements. The results imply that MWCNTs enhanced the impermeability properties of the cementitious composites, and when the w/c ratio increased, the efficiency of the reinforcements was less notable. When extra MC was added into the MWCNT-based cementitious composites, there were two distinct trends: the best water absorption properties of the cement pastes herein appeared at a 0.6 w/c ratio, while the best gas permeability properties herein occurred at a 0.3-w/c-ratio, mainly due to the hygroscopicity of the methylcellulose. The MIP results further suggested that the MC improved the aperture distribution of the MWCNTs in the cementitious composites and greatly optimized the pores from 103 nm to 102 nm at high w/c ratios. SEM images confirmed that the MC increased the viscosity of the fresh cement pastes and inhibited the reagglomeration of the MWCNTs. The findings of this study can guide MWCNT/MC hybrid composite implementation in the future.

Rheological behavior of aqueous mullite-albumin-methylcellulose systems

In this work, the thermogelling behavior of aqueous mullite-bovine serum albumin (BSA) suspensions was studied by dynamic rheology in order to determine the experimental conditions that must be used to form mullite green bodies by thermal consolidation. Viscoelastic properties (G′ and G′′) as a function of temperature (30–95°C) and time were determined by temperature sweep tests and time sweep tests, respectively. On the other hand, the influence of methylcellulose (MC) (2wt%) as a binder on the viscoelastic properties of the aqueous mullite-protein system as a function of both experimental parameters (temperature and time) was also studied. In addition, shear flow properties of aqueous mullite (40vol%; 0.45wt% of polyacrylic polyelectrolyte as a dispersant)–BSA (10 and 15vol%)-MC (2wt%) suspensions were analyzed to obtain information on the rheological behavior of the suspensions at room temperature. The results obtained showed that the presence of mullite particles and MC changed the onset temperature of gelation of the protein and increased the gelation time. Thus, both the mullite particles and methylcellulose intervened in the formation of the developed protein gel.

Influence of methylcellulose on attributes of β-carotene fortified starch-based filled hydrogels: Optical, rheological, structural, digestibility, and bioaccessibility properties

There is considerable interest in controlling the gastrointestinal fate of nutraceuticals to improve their efficacy. In this study, the influence of methylcellulose (an indigestible polysaccharide) on lipid digestion and β-carotene bioaccessibility was determined. The carotenoids were encapsulated within lipid droplets that were then loaded into rice starch hydrogels containing different methylcellulose levels. Incorporation of 0 to 0.2% of methylcellulose had little impact on the dynamic shear rheology of the starch hydrogels, which may be important for formulating functional foods with desirable textural attributes. The microstructure, lipid digestion, and β-carotene bioaccessibility of the filled hydrogels were measured as the samples were passed through simulated oral, gastric, and small intestinal phases. The lipid digestion rate and carotenoid bioaccessibility decreased with increasing methylcellulose. This effect was attributed to the ability of the methylcellulose to inhibit molecular diffusion, promote droplet flocculation, or bind gastrointestinal components thereby inhibiting triacylglycerol hydrolysis at the lipid droplet surfaces. This information may be useful for rationally designing functional foods with improved nutritional benefits.

The influence of methylcellulose (MC) on solubility of calcium hydroxyapatite (HA) crystals in HA/MC nanocomposites

The influence of methylcellulose ([C6H7O2(OH)3–x(OCH3)x]n, MC) on the morphology and solubility of calcium hydroxyapatite (Ca10(PO4)6(OH)2, GA) nanocrystals (NCs) in GA/MC organomineral nanocomposites (OMCs) is studied. GA/MC OMCs with the MC content of 0.5, 1, 2, 5, 10 and 20 wt % are synthesized in the Ca(OH)2–H3PO4–[C6H7O2(OH)3–x(OCH3)x]n–H2O system under biomimetic conditions (37°C). The composition and structural features of OMCs, as well as crystallographic characteristics, size, and morphology of GA NC in OMCs, are determined via chemical analysis, X-ray diffraction (XRD), infrared spectroscopy (IRS), thermal analysis (DTA and DTG), scanning (SEM) and transmission (TEM) electron microscopy, and electron diffraction (ED). It is shown that the growth in the MC concentration in OMCs leads to the change in the GA NC morphology and the increase in their solubility (for Ca2+ and PO43- ions).

Effect of Viscosity on Particle Size, Deposition, and Clearance of Nasal Delivery Systems Containing Desmopressin

The effect of methylcellulose on the particle size distribution and dosing accuracy of pre-metered spray pump devices containing the peptide desmopressin (DDAVP) was investigated. Using gamma scintigraphy, the influence of methylcellulose on the in vivo deposition and clearance of nasal solutions administered as drops or spray was studied. Nasal formulations containing 0, 0.25, and 0.50% methylcellulose produced a dose-related increase in average particle size from 51 μm for 0% to 81 and 200 μm for 0.25 and 0.50% methylcellulose, respectively. However, no effect was observed on the dosing accuracy of the spray pumps. The addition of methylcellulose gave a more localized in vivo deposition in the anterior region of the nasal vestibule. However, the net effect on clearance followed a biphasic pattern which showed an increase in retention time for the 0.25% solution, followed by a decrease in retention time and faster clearance time for the 0.50% solution. The spray delivers well-controlled doses to the nasal cavity. These findings show that viscosity, particle size, and nasal clearance are important parameters in the design of nasal delivery systems.

Time Factor and Minima in Tension Curves

IN an investigation of the influence of methylcellulose on the interfacial tension between cyclohexane and water1, a modified drop-volume method2 similar in principle to the drop-weight method described by Addison3 was employed to study the time factor. The relationships found between interfacial tension and time were essentially of the same form as obtained by Addison3 in the case of surface tension, but minima were observed in these tension - time curves, which are displaced towards zero time and become more pronounced as the concentration increases. Such minima have also been observed in surface tension - time curves4.