Hydroxypropyl Methylcellulose Concentration Research Articles

Formulation and Evaluation of Polyherbal Antidandruff Shampoo

The aim of the present work was to develop the polyherbal antidandruff shampoo and evaluate the formulated shampoos for physical parameters. Shampoos are the products which are used for the removal of the dirt and surface grease from the hair shaft and scalp. Dandruff is a common disorder affecting the scalp condition caused by yeast Pityrosporum. To treat the dandruff the polyherbal antidandruff shampoos were prepared using plant extract namely Murraya koenigi (Curry leaves), Hibiscus Rosa sinesis (Hibiscus), Mentha piperita (Mint) and other ingredients required for shampoo base. The plant extract were prepared by using cold maceration process. The polyherbal shampoo formulations included ingredients, Curry leaves extract, Mint extract, Hibiscus extract, Sodium lauryl sulphate, Sodium citrate, Hydroxy propyl methyl cellulose, Glycerin, Methyl paraben, Propyl paraben, Perfume, Distilled water. A total of four formulations were made with varying concentrations of Hydroxy propyl methyl cellulose (HPMC) and Sodium citrate. The formulation was then evaluated by several tests like visual inspection, pH, percentage of solids contents, dirt dispersion, viscosity, foaming ability and foam stability, wetting time, surface tension, washability, spreadability, antimicrobial activity, etc. All the formulations showed satisfactory results. The formulation F3 having varying concentrations of HPMC and Sodium citrate showed significant results in comparison to other formulations. The outcome of the present studies revealed that polyherbal shampoos can be prepared easily from the natural plant sources having antimicrobial properties and herbal antidandruff shampoos are better alternatives than synthetic shampoos.

Anti-dispersion, rheological, and mechanical properties of GBFS/FA geopolymer for underwater engineering applications

Cementitious materials used in underwater engineering primarily face challenges such as water infiltration, chloride ion penetration, and sulfate attack. Therefore, the use of fast curing, strong corrosion resistance, and high-performance geopolymers is critical in underwater engineering. In this study, NaOH was selected as the activator, with granulated blast furnace slag (GBFS) and fly ash (FA) serving as precursors. The effects of hydroxypropyl methylcellulose (HPMC) content, alkali content, and the GBFS/FA ratio on the anti-dispersion, rheological, and mechanical properties of the geopolymers were systematically investigated. The results indicated that when the Na₂O content was below 5 wt%, increasing the HPMC enhanced the anti-dispersion properties of the geopolymer paste. However, in a highly alkaline environment (Na2O≥7 wt%), HPMC did not enhance the anti-dispersion properties of the paste. Infrared spectrum analysis suggested that the degradation of HPMC chemical bonds was responsible for the loss of underwater anti-dispersion properties in the geopolymer paste. The workability of the paste was negatively impacted by the thickening effect of HPMC. As the HPMC content increased, both the yield stress and plastic viscosity of the paste rose. FA enhanced the paste's workability, increasing its flowability by 13.36 %. At a constant alkali content, the rheological behavior of the paste was significantly affected by the HPMC content and the GBFS/FA ratio. The Bingham and modified Bingham (MB) models were employed to fit the rheological curve of the geopolymer paste, yielding satisfactory results. While GBFS contributed to the improvement of early strength, FA had a contrary effect. HPMC could delay the hydration process, increase the porosity of geopolymers, and reduce the strength of the samples. Underwater pouring further exacerbated the porosity, negatively affecting the geopolymer's strength. This study offers valuable insights for the application of geopolymers in underwater engineering.

Implementing the Design of Experiments (DoE) Concept into the Development of Mucoadhesive Tablets Containing Orange Peel Extract as a Potential Concept for the Treatment of Oral Infections.

This study explores for the first time the impact of chitosan (CS) with varying molecular weights (MW), orange peel extract concentration, and hydroxypropyl methylcellulose (HPMC) content on the formulation of buccal tablets for treating oral infections. Utilizing a statistical design of experiments (DoE), nine different formulations were evaluated for mechanical properties, dissolution behavior, mucoadhesion, and biological activity. A formulation with high CS MW, 60% orange peel extract, and 8% HPMC, emerged as the optimal formulation, demonstrating superior tabletability, compressibility, and compactibility. Dissolution studies indicated that hesperidin release followed the Higuchi model, with higher extract content enhancing this phenomenon. Mucoadhesion improved with increased HPMC and CS concentrations, although higher extract content reduced bioadhesion. Biological assays showed that higher extract levels boosted antioxidant activity, while CS primarily contributed to anti-inflammatory effects. The optimized formulation exhibited broad antimicrobial activity against key oral pathogens, surpassing the effectiveness of the individual components. Principal component analysis (PCA) further confirmed the significant influence of extract content on tablet properties. These findings suggest that the optimized tablet formulation holds promise for effective buccal delivery in the treatment of oral infections, warranting further investigation in clinical settings.

HPMC-Zein Film-forming Gel Loaded with 5-Fluorouracil Coupled with CO2 Laser Dermabrasion for Managing Stable Vitiligo.

Vitiligo is a significant dermatological challenge affecting 0.5 to 2% of the global population. Despite the various existing medical approaches, current vitiligo treatments are far from ideal. The present study aimed to prepare and evaluate a film-forming gel of 5 fluorouracil (5FU) using different ratios of hydroxypropyl methylcellulose (HPMC) and Zein for treating vitiligo. The prepared film-forming gels were fully characterized in terms of morphology, Fourier-transform infrared spectroscopy, drug content, pH, drying time, in-vitro drug release, and clinical investigation. A 32-full factorial design was used to study the impact of varying concentrations of HPMC (X1) and Zein (X2) on the percentage of 5FU released (Y1) from the prepared film-forming gels. Scanning electron microscopy (SEM) revealed a cross-linked network structure between polymers. An increase in HPMC concentration (2-4%) correlated with higher 5FU release, whereas increased Zein concentration (1-2%) resulted in reduced 5FU release. Furthermore, patients treated with 5FU film-forming gel after dermabrasion with fractional CO2 (FCO2) laser exhibited a significant decrease in JAK3 gene expression and higher effectiveness than those treated with FCO2 laser alone. Our results suggest that the film-forming gel of 5FU is promising as an effective formulation for treating vitiligo.

A novel mucoadhesive film containing probiotic extract for oral candidiasis treatment: Formulation and antifungal evaluation

Probiotic strains offer a novel and potentially effective approach to treat oral candidiasis. Buccal mucoadhesive films have attracted considerable attention in recent years due to their unique ability to adhere and persist on the oral mucosa, while gradually releasing their encapsulated drug content. Therefore, the aim of the study was to develop mucoadhesive films containing probiotic extract for treatment of oral candidiasis. Mucoadhesive films were fabricated with hydrophilic polymers, such as polyvinyl alcohol (PVA) and hydroxy propyl methyl cellulose (HPMC). Then, films were evaluated regarding their thickness, pH, tensile strength and elongation, swelling, in vitro release and antifungal activity. The type of polymer used had an impact on the mechanical properties, swelling and release of the films. Films prepared using PVA showed significantly higher tensile strength and elongation at break values compared to those prepared using HPMC. However, swelling index increased with enhancing HPMC concentration in the films. The release of probiotic extract from the film prepared with HPMC occurred slowly. Based on these results, films containing 54 % HPMC and 26 % PVA were selected as optimal formulation. Moreover, it was found that optimal film containing probiotic extract could inhibit the growth of Candida albicans. Regarding to the obtained results, probiotic oral adhesive mucoadhesive films can be considered as a promising alternative to traditional methods in the treatment of candidiasis.

Review of Hydroxypropyl Methylcellulose in Artificial Tears for the Treatment of Dry Eye Disease.

Dry eye disease (DED) is a highly prevalent condition, resulting in reduced quality of life, lower participation in social life and impaired work efficiency. Hydroxypropyl methylcellulose (HPMC) is a cellulose-based viscosity-enhancing agent and is one of the most popular therapeutic ingredients in artificial tears. This review aims to evaluate the literature on the efficacy and safety of HPMC used in the treatment of DED. Literature searches were conducted in PubMed and Cochrane CENTRAL. A total of 28 clinical trials from 26 publications are included in this review, including 21 clinical intervention studies evaluating the effect of HPMC treatment over time and seven single instillation studies evaluating the short-term physical and symptomatic effects of HPMC after drop-instillation. The duration of clinical intervention studies ranged from 2 weeks to 5.5 months. DED severity ranged from mild to severe. Drop frequency ranged from two to up to 16 drops per day. HPMC concentration in artificial tears ranged from 0.2% to 0.5%. No major complications or adverse events were reported. Artificial tears containing HPMC were effective at improving symptoms and some signs of DED. However, combination drops with HPMC plus other therapeutic ingredients seem more effective than HPMC alone. HPMC appears to be equally effective or inferior to hyaluronic acid (HA). There is no evidence of superiority or inferiority to either carboxymethylcellulose (CMC) or polyethylene glycol 400/propylene glycol (PEG/PG). No single study explained the choice of drop frequency or HPMC concentration. More well-designed studies are needed to determine an evidence-based standard for HPMC treatment, including drop frequency, concentration and molecular weight for different DED severity and subgroups.

Influence of CMC, HPMC, and CNF on Performance of Corrugated Base Paper

AbstractThis study aims to comprehensively examine the influence of three distinct additives, namely carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC), and cellulose nanofibers (CNF), on the performance enhancement of corrugated base paper. For this purpose, steam‐exploded rice straw was treated with varying concentrations (2, 4, 6, 8, and 10 wt%) of CMC, HPMC and CNF. Analysis of the rice straw pre and post expansion, as well as the modified corrugated base paper, was conducted using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), tensile performance testing, and scanning electron microscopy (SEM). Results indicated that adding CMC, CNF, and HPMC to corrugated base paper significantly improved bonding between paper layers, particularly at 2 %, 6 %, and 8 % concentrations, respectively. This enhancement notably increased tensile strength and elastic modulus of the corrugated base paper. Tensile performance saw increases of 57.76 %, 59.01 %, and 60.25 %, while elastic modulus showed increments of 52.7 %, 9.4 %, and 136.69 %, respectively. These findings provide valuable insights for the preparation of corrugated base paper and highlight the potential of CMC, HPMC, and CNF in enhancing paper mechanical properties.

Formulation and Evaluation of Bilastine Thermosensitive Mucoadhesive Ophthalmic in situ Gel

Background: Bilastine is a non-sedating, second-generation antihistamine used to treat urticaria and allergic conjunctivitis. Objective: to formulate and test bilastine as a mucoadhesive ophthalmic in situ gel in order to extend its presence at site for longer time and help treat conjunctivitis and allergic rhinitis. Methods: We prepared formulations using different concentrations of poloxamers (Poloxamer 407 (P407) and Poloxamer 188 (P188)) in combination with hydroxypropyl methyl cellulose (HPMC). The prepared formulas were evaluated for their physicochemical properties, sol-gel transition temperature, viscosity, mucoadhesive strength, drug release, and kinetic modeling. Results: The prepared in situ gels were clear and transparent, having a pH ranging from 7.4 to 7.5 and a gelation temperature between 29.5 and 34.7 °C. Increasing the concentrations of P-407 and HPMC increased viscosity, gel strength, and mucoadhesion force, but caused a decrease in gelation temperature and drug release. Formula (F 14) containing P 407/P 188/HPMC as 19/4/0.75% w/v, respectively, exhibited favorable characteristics, including optimal gelation temperature (33°C), drug content (93%), gel strength (40 sec), mucoadhesive force (6125 dyne/cm2), and 91.4% in vitro drug release over 5 hours. Conclusions: The bilastine mucoadhesive in situ gel formulation is presented as a promising ophthalmic formulation for the treatment of allergic conjunctivitis.

High-performance biodegradable triboelectric nanogenerators based on hydroxypropyl methylcellulose and zinc oxide hybrid composites

The increasing demand for sustainable energy solutions has ignited strong interest in developing biodegradable Triboelectric Nanogenerators (B-TENGs), representing a paradigm shift toward eco-friendly power generation. Our research seeks to lead this transformative endeavor, aiming to address existing challenges and advance the field of B- TENG technology. We investigate a hybrid composite composed of Hydroxypropyl Methylcellulose (HPMC) and Zinc Oxide (ZnO) nanoparticles, emphasizing sustainability and biodegradability. By optimizing the HPMC matrix, we increase power output while maintaining biodegradability and adjust the HPMC content to achieve a balance between performance and flexibility. Our results show significant improvements in TENG output, with the 1 % HPMC: ZnO composite delivering the highest performance: a maximum voltage of 39.8 V, a current of 4.38 μA, and a power density of 0.23 W/m². Additionally, the composite films display excellent biodegradability, fully degrading in water within 36 h, demonstrating their promise for sustainable applications. These groundbreaking advancements highlight the potential of biodegradable TENGs to transform energy harvesting, providing a sustainable solution across multiple industries and setting the stage for a greener future for generations to come.

FORMULASI DAN UJI SIFAT FISIK PERMEN EDIBLE FILM EKSTRAK ETANOL DAUN SAGA (Abrus precatorius L)

The fungus Candida albicans is one of the causes of mouth ulcer whose growth can be inhibited through the activity of saga leaf extract which contains saponin and flavonoid compounds. One of the efforts to facilitate the use of ethanolic extract of saga leaves is to make it into edible film candy preparations. This study aims to evaluate the physical properties of edible film candies containing an ethanol extract of saga leaf with varying concentrations of hydroxypropyl methylcellulose (HPMC). The ethanol extract of saga leaves was prepared using the maceration method with 70% alcohol, resulting in a 5% concentration of ethanol extract of saga leaves. The HPMC concentrations used varied between 3.5%, 2.5%, and 1.5%. Subsequently, the resulting edible film underwent physical property tests, including organoleptic evaluations, moisture content, pH, thickness, weight determination, and dissolution time. The analysis revealed that the edible film exhibited a thin shape and a blackish-green color, along with a distinctive aroma of the extracts and sweet, bitter, and minty flavors. The pH of the edible film was 6, with a moisture content of less than 20%, and a fold resistance of less than 100. Moreover, it only melted without dissolving. Statistical analysis demonstrated a significant difference in the thickness and weight of the edible film among the variations in HPMC concentration. In conclusion, the comparison of HPMC concentration affects the physical properties of edible film candy containing ethanol extract of saga leaves, and HPMC concentration of 2.5% is a suitable choice to meet the requirements of edible film according to the Indonesian National Standard (SNI).

Effect of hydroxypropyl methyl cellulose on coarse tailings cemented backfill: Rheology, stability, strength and microstructure

The bleeding and segregation of coarse tailings cemented backfill (CTCB) seriously affect the effect of roof-contacted filling, and may even lead to safety hazards in mining. The incorporation of hydroxypropyl methyl cellulose (HPMC) may be an effective solution, but its impact on the performance of CTCB and its underlying mechanism remains inadequately understood. This study comprehensively evaluates the rheology (static and dynamic yield stress, and plastic viscosity), stability (bleeding and permeability), strength, and microstructure of containing HPMC. In addition, the mechanism of HPMC on CTCB was further investigated. The research results show that a certain amount of HPMC (<0.1%) can significantly reduce the dynamic and static yield stress of fresh CTCB, while the plastic viscosity increases with the HPMC content. Furthermore, HPMC can significantly improve the bleeding and segregation of CTCB through association and network structure effects. Finally, HPMC delays the hydration of cement, resulting in an early strength reduction of CTCB, but it has little impact on the strength at 28 days.

Drying kinetics modeling of hot air drying of emulsion templated oleogels employing hydroxypropyl methylcellulose as structuring agent

This work focused on the drying of O/W emulsions employed to obtain templated structured oils with hydroxypropyl methylcellulose (HPMC) as oleogelator. Sunflower oil/water emulsions with different HPMC content (1%–3% w/w) were dried at different air temperatures (from 70 to 100 °C) employing two different initial thicknesses (0.25 and 0.50 cm). Drying kinetics showed the existence of an initial constant drying rate period followed by a falling drying rate period below critical moisture content. This critical content was constant (0.38 kg water/kg dry solid) independently of drying conditions and HPMC content. Drying rate decreased linearly with moisture content during the falling rate periods. A 3-parameter model was proposed to simulate drying kinetics in the range of drying temperature and HPMC content of tested oleogels. Physical properties of fresh and stored (20 days) oleogels such as oil binding capacity, color, and hardness were measured to evaluate drying conditions effect on product quality. Temperatures above 70 °C were necessary to promote the HPMC gelation. Best characteristics of oleogels in terms of texture, color and oil binding capacity were obtained with HPMC content of 2% w/w, 0.25 cm of emulsion thickness and 80 °C of drying temperature. These results are useful for the design of large-scale dryers for this new kind of products.

Optimization of Hydroxypropyl Methylcellulose (HPMC) and Carbopol 940 in Clindamycin HCl Ethosomal Gel as Anti-acne

Clindamycin HCl has anti-acne properties because it can inhibit the growth of Propionibacterium acnes (P. acnes) bacteria. However, the bioavailability of clindamycin HCl is less than 13% of the given dose, so it needs to be developed in the form of ethosomes to increase its bioavailability. This study aimed to create a clindamycin HCl ethosomal gel preparation with varying hydroxypropyl methylcellulose (HPMC) and carbopol-940 as a gelling agent using a factorial design to obtain 4 formulas. The concentrations of HPMC and carbopol 940 used were 0.5% and 1%. The optimum formula was determined based on the pH response, viscosity, spreadability, and adhesion of the clindamycin HCl ethosomal gel preparation. Based on the factorial design analysis, HPMC and Carbopol-940 have an influence on the pH response and adhesion, while the interaction between HPMC and Carbopol-940 influences the spreadability and viscosity responses. The optimum formula was obtained with a desirability value of 0.994 at a concentration of HPMC was 1%, and Carbopol 940 was 0.5%. The minimum inhibitory concentration of the optimum clindamycin HCl ethosomal gel was 60 µg/mL. So, the clindamycin HCl ethosomal gel had a strong antibacterial activity.

The effect of hydroxy propyl methyl cellulose on emulsion stability and sensory properties of virgin coconut oil mayonnaise

Mayonnaise is a semi-solid emulsion made by mixing ingredients such as vegetable oil, egg yolks, and other food ingredients with or without adding food additives, such as stabilizers. This research aimed to study the effect of hydroxypropyl methylcellulose (HPMC) on the emulsion stability and sensory properties of mayonnaise made from virgin coconut oil. In this study, the treatment was the addition of HPMC, namely MV1 (0%), MV2 (2%), MV3 (3%), MV4 (4%), and MV5 (5%), into the mayonnaise formulation. The data obtained were analyzed statistically using analysis of variance and continued with DNMRT at the 5% level. The analysis of variance showed that the HPMC concentration significantly affected emulsion stability, viscosity, degree of acidity, and sensory test of thickness but had no significant effect on the aroma, color, and taste of the mayonnaise. The best treatment was MV5 (5% HPMC), which had 100% emulsion stability, 70119.33 cP viscosity, 5.07 pH on day one, and 99.37% emulsion stability, 69047.33 cP viscosity, and 4.87 pH on day 15. The MV5 mayonnaise was yellowish, had a coconut taste, was slightly rancid, and was thick. The MV5 mayonnaise was more favorable than other treatments regarding the aroma, color, and taste of the mayonnaise.

Comparing the Performance of Raman and Near-Infrared Imaging in the Prediction of the In Vitro Dissolution Profile of Extended-Release Tablets Based on Artificial Neural Networks.

In this work, the performance of two fast chemical imaging techniques, Raman and near-infrared (NIR) imaging is compared by utilizing these methods to predict the rate of drug release from sustained-release tablets. Sustained release is provided by adding hydroxypropyl methylcellulose (HPMC), as its concentration and particle size determine the dissolution rate of the drug. The chemical images were processed using classical least squares; afterwards, a convolutional neural network was applied to extract information regarding the particle size of HPMC. The chemical images were reduced to an average HPMC concentration and a predicted particle size value; these were used as inputs in an artificial neural network with a single hidden layer to predict the dissolution profile of the tablets. Both NIR and Raman imaging yielded accurate predictions. As the instrumentation of NIR imaging allows faster measurements than Raman imaging, this technique is a better candidate for implementing a real-time technique. The introduction of chemical imaging in the routine quality control of pharmaceutical products would profoundly change quality assurance in the pharmaceutical industry.

Study on the Leaching Kinetics of Weathered Crust Elution-Deposited Rare Earth Ores by Hydroxypropyl Methyl Cellulose

In the process of the in situ leaching of weathered crust elution-deposited rare earth ores (WCE-DREOs), there are many problems in the conventional leaching agent, such as a slow leaching rate, low leaching yield and long leaching period. In order to solve the above problems, 2.0 wt% ammonium sulfate was mixed with hydroxypropyl methyl cellulose (HPMC). The effects of the HPMC concentration, temperature, pH and flow rate on the leaching kinetics of rare earth (RE) and aluminum (Al) were investigated. The results showed that when the concentration of HPMC was 0.05 wt%, the leaching equilibrium time of RE and Al was about 60% shorter than that of single ammonium sulfate. With an increase in the leaching temperature, the leaching equilibrium time of RE and Al decreased, and the apparent activation energy of RE and Al was 23.13 kJ/mol and 17.31 kJ/mol, respectively. The leaching process was in line with the internal diffusion kinetic control model. When the pH of the leaching agent was 4.02~8.01, the leaching yield of RE and Al was basically the same, but the leaching yield of Al was greatly increased at pH 2.0 due to a large amount of adsorbed hydroxy-Al in the RE ore eluded. The leaching yield reached the maximum when the flow rate was 0.7 mL/min. The leaching time and the leaching cost of RE can be saved by the composite leaching agent. The results provide theoretical guidance for the development and industrial application of the new composite leaching agent.

Effect of silica fume and PCE-HPMC on LC3 mortar: Microstructure, statistical optimization and life cycle Assessment

With immense carbon emissions, the cement and concrete industries account for nearly eight percent of the world’s total. As the demand for urbanisation increases, the carbon footprint of the industry will also increase rapidly. A sustainable and greener low carbon cement called limestone calcined clay cement (LC3) is being developed as a promising alternative to ordinary Portland cement (OPC). The present study investigates the effects of silica fume (SF) on LC3 with variable dosages of polycarboxylate ether-based superplasticizer (SP) and hydroxypropyl methylcellulose (HPMC) admixtures. Using three level-three factorial (33) Box Behnken Design and response surface methodology (RSM), SF content, SP content, HPMC content, and flow value were set as input parameters to optimise and evaluate the eight output response parameters, namely, water binder (w/b) ratio, compressive strength (7 and 28 days), modulus of rupture, porosity, water absorption, ultrasonic pulse velocity, and water sorptivity. With a combined desirability of 90.8% for an optimised mix, the model showed that with 0% SF, 0.811% SP, 0.923% HPMC, and 124.12 mm of FV, a LC3-50-based cement system with higher physico-mechanical properties can be developed. The microstructural analysis was also conducted through a scanning electron microscope (SEM), Thermogravimetric Analyzer (TGA), and X-ray diffraction (XRD). The results showed Calcium silicate hydrate (C-S-H) development along with consumption of portlandite (CH) for LC3-50-based cement systems. Sustainability analysis of LC3-based mortar in terms of carbon emissions showed a 33.82% reduction in CO2 emissions as compared to OPC.

Mechanisms of swelling inhibition and seepage promotion of weathered crust elution-deposited rare earth ore by hydroxypropyl methyl cellulose

In-situ leaching process of weathered crust elution-deposited rare earth ore (WCE-DREO) often faces problems such as poor permeability and occurrence of landslides. The main reasons are the swelling of clay minerals by water absorption and blockage of seepage channels by fine particles. This study proposed using hydroxypropyl methyl cellulose (HPMC) as a novel green swelling inhibitor with the combination of ammonium sulfate ((NH4)2SO4) as an efficient composite leaching agent. The swelling inhibition performance of HPMC on swelling inhibition was evaluated through linear swelling tests and mud ball immersion tests. The mechanisms of HPMC on swelling inhibition and seepage promotion were analyzed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Scanning electron microscopy (SEM), Surface area analysis (BET), X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA), and the contact angle, zeta potential and particle size distribution were characterized. The results indicated that HPMC showed a good performance on swelling inhibition, which improved with the increase of HPMC concentration. HPMC expels the water from the interlayer. Moreover, HPMC adsorbs onto the surface of clay minerals by hydrogen bonding to form a hydrophobic film, which can prevent the clay minerals from hydration swelling. Due to the electric neutrality property of HPMC, the electrostatic repulsion of clay minerals can be reduced. Therefore, the fine particles of the clay minerals can be bridged to form larger particles by the long carbon chain of HPMC which leads to expansion of the seepage channels as well as the improvement of the permeability of the ores. According to the column leaching tests, the novel leaching agent composed of 0.05 wt% HPMC and 2 wt% (NH4)2SO4 not only showed a good leaching capacity of rare earth, but also inhibited the swelling of clay and enhanced the seepage when comparing with traditional leaching agent ((NH4)2SO4). Developing a novel leaching agent benefits the green, safe and high-efficiency exploitation of WCE-DREO.

Effects of hydroxypropyl methylcellulose on anti-dispersion and rheology of alkali-activated materials in underwater engineering

To explore the feasibility of applying alkali-activated materials (AAM) to underwater engineering. The effects of hydroxypropyl methylcellulose (HPMC) on the anti-dispersion and rheological properties of AAM were investigated. NaOH was selected as the activator, and granulated blast furnace slag (GBFS) and fly ash (FA) were used as precursors. The characteristics of anti-dispersion, rheology, and hydration heat change of alkali-activated slurry with 6 kinds of HPMC content (0, 0.2%, 0.4%, 0.6%, 0.8%, and 1%) and 4 kinds of alkali content (Na2O: 3%, 5%, 7%, and 9%) were discussed. The anti-dispersion was characterized by turbidity. The fluidity, gel time, yield stress and plastic viscosity were obtained from rheological tests. The hydration heat was measured by isothermal calorimetry. The results show that HPMC can improve the anti-dispersion of alkali-activated slurry with alkali content (Na2O: 3%, 5%), and the effect was good when the content exceeded 0.6%. Compared with that without HPMC, the turbidity was reduced by 98.4% at 1% HPMC content. With the increase of HPMC, the fluidity and gel time decreased, and the yield stress and plastic viscosity increased at the initial stage. The fluidity of alkali-activated slurry decreased by 23% and the plastic viscosity increased by 916%. It is due to the thickening effect of HPMC, which can change the anti-dispersion and rheology of slurry. The mechanism of HPMC can increase the attraction between raw material particles, and the molecular chains overlap to form a network structure that can wrap the alkali-activated slurry. The evolution of shear stress and hydration heat show that HPMC can delay the hydration reaction of AAM. When the alkali content is high (Na2O: 7%, 9%), HPMC has no obvious improvement in the anti-dispersion of alkali-activated slurry. The increase of HPMC content has no effect on the yield shear stress and plastic viscosity at the initial stage. It shows that HPMC fails at high Na2O content, which leads to loss of thickening effect. The paper is expected to guide for using HPMC in underwater engineering to improve the anti-dispersion and workability of AAM.

Formulasi Dan Uji Fisikokimia Gel Sleeping Mask Ekstrak Kulit Buah Naga Merah Dengan Variasi Gelling Agent Hydroxypropyl Methly Cellulose (HPMC)

Gels are semi-solid preparations formed from suspensions made up of large organic molecules and small inorganic particles that permeate the liquid. Sleeping mask It is a skin care product that is used at night (before going to bed). Serious research on natural ingredients is currently being carried out, including research in the field of cosmetics. Among the advantages of natural ingredients is their antioxidant properties, which can disrupt free radicals and cause the use of antioxidants in preventing premature aging. Dragon fruit skin contains compounds polyphenol, anthocyanins and betacyanins which have antioxidant activity. This study aims to determine the effect of the gelling agent Hydroxypropyl Methylcellulose (HPMC) on the physical properties of gel preparations sleeping mask red dragon fruit skin extract. This study uses an experimental method. Red dragon fruit skin is extracted by maceration in 96% ethanol. This study used 3 gel formulations, with various concentrations of HPMC 5%, 7% and 9%. Physicochemical tests carried out included organoleptic tests, homogeneity, pH, spreadability, adhesion, irritation and viscosity. The results of the research show the use of variations gelling agent HPMC meets the criteria for the physicochemical test of gel preparations sleeping mask from dragon fruit skin extract which produces the best formula from gel preparations sleeping mask namely formulation III (9%) has the best evaluation.