Viscosity Grade Research Articles

Performance analysis of journal bearing operating on nanolubricants with TiO2, CuO and Al2O3 nanoparticles as lubricant additives

Present experimental study investigate the performance analysis of Journal bearing operating on Nanolubricants prepared by adding TiO2, CuO and Al2O3 nanoparticles as lubricant additives in Avalon ISO Viscosity grade 46 oil. By adding nanoparticles, the viscosity of the lubricant oil is improved, and, in effect, a performance characteristic of journal bearing is enhanced. Nanoparticles used for present work is mixed with base oil with volume fractions of 0.25%, 0.5%, 1% and 2% with the help of mechanical agitator and ultrasonication. Journal bearing Test Rig TR-60 is used to experimentally investigate pressure distribution and load carrying capacity. Performance of bearing is measured at speeds 250 rpm, 500 rpm and at loads 300 N and 450 N. The results indicate a rise in maximum pressure and load carrying capacity of journal bearing by adding TiO2, CuO, and Al2O3 nanoparticles as lubricant additives compared to base oil without nanoparticles additives.

The Influence of Temperature and Viscosity of Polyethylene Glycol on the Rate of Microwave-Induced In Situ Amorphization of Celecoxib

Microwaved-induced in situ amorphization of a drug in a polymer has been suggested to follow a dissolution process, with the drug dissolving into the mobile polymer at temperatures above the glass transition temperature (Tg) of the polymer. Thus, based on the Noyes–Whitney and the Stoke–Einstein equations, the temperature and the viscosity are expected to directly impact the rate and degree of drug amorphization. By investigating two different viscosity grades of polyethylene glycol (PEG), i.e., PEG 3000 and PEG 4000, and controlling the temperature of the microwave oven, it was possible to study the influence of both, temperature and viscosity, on the in situ amorphization of the model drug celecoxib (CCX) during exposure to microwave radiation. In this study, compacts containing 30 wt% CCX, 69 wt% PEG 3000 or PEG 4000 and 1 wt% lubricant (magnesium stearate) were exposed to microwave radiation at (i) a target temperature, or (ii) a target viscosity. It was found that at the target temperature, compacts containing PEG 3000 displayed a faster rate of amorphization as compared to compacts containing PEG 4000, due to the lower viscosity of PEG 3000 compared to PEG 4000. Furthermore, at the target viscosity, which was achieved by setting different temperatures for compacts containing PEG 3000 and PEG 4000, respectively, the compacts containing PEG 3000 displayed a slower rate of amorphization, due to a lower target temperature, than compacts containing PEG 4000. In conclusion, with lower viscosity of the polymer, at temperatures above its Tg, and with higher temperatures, both increasing the diffusion coefficient of the drug into the polymer, the rate of amorphization was increased allowing a faster in situ amorphization during exposure to microwave radiation. Hereby, the theory that the microwave-induced in situ amorphization process can be described as a dissolution process of the drug into the polymer, at temperatures above the Tg, is further strengthened.

Application of quality by design paradigm in the design of muco-adhesive extended release film for oral ulcer

The present study deals with the formulation of mucoadhesive bilayered buccal film of lidocaine hydrochloride and benzydamine hydrochloride for treatment of oral ulcers (aphthous stomatitis). Eudragit-RLPO and Ethyl cellulose were used as film forming polymers and low viscosity grade hydroxyl propyl cellulose as a mucoadhesive agent. Solvent casting method was adopted for film formation. The film was evaluated for content uniformity, tensile strength, folding endurance, swelling, mucoadhesive strength, ex vivo mucoadhesive time and in vitro drug release. The films were characterized for DSC and FTIR. The film showed acceptable film properties and muco-adhesion. The formulation showed predictive drug release, i.e. 80 in 2, 4 and 6 h respectively. In-vitro drug release study revealed that a combination of Eudragit and Ethyl cellulose was required for better control of the drug release. The DSC and FTIR study confirmed drug-drug and drug–excipient compatibility. Keywords: Bilayer film, Eudragit-RLPO, Ethyl cellulose, Muco-adhesion, Extended drug release.

Coupled effects of warm mix asphalt (WMA) additives and rheological modifiers on the properties of asphalt binders

Asphalt pavements, as an essential element affecting the economic vitality of the countries, are widely used to construct the highways and expressways. Severe climate conditions and traffic loads can influence the service life of asphalt pavements and lead to distresses such as thermal cracking and rutting. Various types of modifiers are used in asphalt industry to enhance the resistance of the pavements to these distresses. Although these modifiers improve a wide range of physical and rheological properties, they increase the construction temperatures, leading to increased energy usage and greenhouse gas emissions. The warm mix asphalt (WMA) technologies provide several techniques and additives to reduce the construction temperature of asphalt pavements and decrease the required energy and air pollution in construction phase. This research aims to investigate the influence of Sasobit and Evotherm M1, as two of the commonly used WMA additives, on the performance of unmodified and modified binders. Three types of modifiers (i.e., polyphosphoric acid (PPA), styrene-butadiene-styrene (SBS), and ground tire rubber (GTR)) were used to modify the binders. The influence of modification on the performance of binders was evaluated through some conventional tests such as viscosity, softening point, and penetration grade. Moreover, the performance grading (PG) tests were conducted at a broad range of service conditions. The results indicate that, with some slight variations, the effects of WMA additives on rheological properties have insignificant dependency on the type of modification. Overall, Sasobit increases the stiffness of binders while Evotherm M1 shows negligible effects on the stiffness properties.

Experimental investigation and process simulation of biolubricant production from waste cooking oil

Waste cooking oil (WCO) or frying oil was used for synthesis of biolubricant via transesterification reaction. Biolubricant (dioleoyl ethylene glycol ester) was prepared from fatty acid methyl esters (FAMEs) of WCO with ethylene glycol (EG). The reaction was performed using calcium oxide (CaO) heterogeneous catalyst. Dioleoyl ethylene glycol ester is a potential biodegradable lubricant that could be used in industrial lubricant applications. The effect of changing operating conditions such as temperature, molar ratio of reactants, reaction time and catalyst loading was studied. The optimal conditions that achieved highest conversion were found to be 130 °C, 3.5: 1, 1.5 h and 1.2% (w/w) catalyst dosage. The produced biolubricant structure was tested using FTIR spectrum technique and its thermal stability was examined using TGA technique. The biolubricant properties were compared to two other biolubricants and also to specifications of four different ISO viscosity grade lubricants. It was found that produced biolubricant complies with ISO VG68 viscosity grade with better low temperature applicability. The process simulation was performed on Aspen HYSYS program version 9 using conversion reactor model and using Non-Random Two-Liquid (NRTL) activity coefficient model. Simulation results proved that the studied biolubricant production process is industrially applicable.

Non-combustible, optically transparent polycarbonate compositions

A brief review of the results of research on reducing the flammability of modified materials based on polycarbonate, the effect of flame retardants and additives that reduce dropping, as well as affecting the complex of properties of polycarbonate is presented. The optimal concentrations of modifying additives for obtaining fire-resistant compositions with high optical characteristics have been determined. It is shown that to achieve the maximum flammability category (PV-0 at a thickness of 2 mm) and oxygen index (42.3%) for thin-walled products, it is necessary to use a high- viscosity grade of polycarbonate (MFI 2.5±1.0 g/10 min), alkali metal sulfonates as a fire retardant and an anti-dripping additive.

FORMULATION DEVELOPMENT OF ORAL FAST-DISSOLVING FILMS OF RUPATADINE FUMARATE

Objective: Rupatadine fumarate (RF) is an anti-allergic drug indicated for the treatment of allergic rhinitis. It has low oral bioavailability due to its poor aqueous solubility and extensive hepatic first pass metabolism. In the present work, oral fast-dissolving films (OFDF) have been formulated and evaluated to facilitate dissolution in the oral cavity itself.
 Methods: Pullulan and HPMC (5, 15 cps) were employed as film formers and six formulations were tried. The physicochemical compatibility between drug and the polymers was studied by FTIR spectroscopy. RF-beta-cyclodextrin (BCD) inclusion complex was initially prepared and evaluated. The inclusion complex was incorporated into the film. OFDF were formulated and prepared by solvent casting method. The film size for one dose was 2 × 2 cm. The films were evaluated for various film parameters including disintegration time and drug release.
 Results: Preliminary film studies indicated % of film former solution to be between 3 and 5% for good appearance, mechanical strength, and quick disintegration. Solubility enhancement of RF is almost 40-fold from its BCD inclusion complex. Drug content in the films ranged between 83 and 90%. The pH ranged between 6 and 7 for all the formulations. All OFDF of RF disintegrated within one minute. With higher viscosity grade of HPMC, disintegration was comparatively slower and so was the drug release. Pullulan based films also showed desirable properties. F3 had disintegration time was 28 s and % drug release was 92% in 180 s.
 Conclusion: OFDF of RF could be formulated employing pullulan and HPMC low viscosity grades by solvent casting method. F3 containing HPMC E5 at 37% by weight of dry film showed desirable film properties. Stability studies indicated that there was no significant change in the films with respect to physicochemical properties and in vitro release.

Static thermal performance evaluation of elliptical journal bearings with nanolubricants

Journal bearings of different configurations have been extensively used in turbomachinery and power generating equipments. Although circular bearings have simplest configuration and commonly used journal bearings, non-circular bearings such as multi-lobe and elliptical bearings have an added advantage of lower lubrication film temperature alongwith stable operation. In this study, static thermal performance of pure elliptical bearing lubricated with nanoparticles based mineral oils has been studied at different eccentricity ratios and bearing speeds. Two types of nanoparticles, namely, CuO and TiO2 with 0.5, 1.0 and 2.0 wt.% concentrations have been separately added in three different viscosity grades of oils. The effect of nanoparticles on thermo-physical properties of oil was considered to compute bearing performance parameters (pressure distribution, load capacity, oil temperature and power losses). Bearing model was generated by taking into account the modified Krieger Dougherty method to determine viscosity at different combinations of oils and nanoparticles. The findings indicate the increase in maximum pressure and load capacity with addition of nanoparticles and this increase was more pronounced at higher concentrations of nanoparticles and at higher viscosity grade oils. Load capacity was found to be increased by 14.24% and 9.21% with 2 wt% concentration of TiO2 and CuO nanoparticles respectively in base oil (AW68) at eccentricity ratio of 0.7. An increase in load capacity with nanolubricants was achieved without an appreciable increase in oil temperature.

Temperature dependent Broadband dielectric relaxation study of Aqueous Polyvinylpyrrolidone (PVP K-15, K-30 & K-90) using a TDR

ABSTRACT Temperature-dependent dielectric relaxation studies of different viscosity grade Polyvinylpyrrolidones (PVP), PVP K-15, PVP K-30 and PVP K-90 having molecular weight 10,000 gmol−1, 40,000 gmol−1 and 360,000 gmol−1 respectively has been done in the frequency region 10 MHz to 50 GHz using Time domain reflectometry (TDR) technique. The frequency-dependent complex dielectric permittivity spectra have been explored by the Havriliak-Negami expression and is explained by the single relaxation model. The PVP molar concentration comprises the concentration domain of 0.0017 ≤ c/M ≤ 0.0176 for PVP-water system. The values of static dielectric constant (ε0), relaxation time (τ) and the empirical parameter (β) have been determined using non-linear least squares fit method along with the thermodynamic properties (activation enthalpy, entropy and free energy) of aqueous solutions of polymers.

Influence of different viscosity grade Methocel and Ethocel polymers for the development of controlled release dimenhydrinate matrix tablets

Dimenhydrinate is a therapeutic agent used for the treatment of nausea and vomiting. A conventional dose of dimenhydrinate is 50 mg per 8 h. Once-daily controlled release tablets of dimenhydrinate were formulated intended to treat emesis. The tablets were formulated using hydrophilic polymers Methocel® and hydrophobic polymers Ethocel® and subsequently analyzed for pre-compression and post-compression characteristics, % moisture uptake, dissolution profiles and release behavior of the drug. Identification of active ingredient and compatibility of blends were analyzed through FT-IR. Drug release kinetics of dimenhydrinate was assessed at pH 1.2, 4.5 and 6.8. The results of release profiles were evaluated for different kinetic models including model dependent and model independent. The optimized formulation K100M 30% showed ideal pre-compression properties and in vitro characteristics. Tablets exhibited a controlled drug release pattern due to the formation of a viscous gel layer followed by erosion. Furthermore, zero-order best described the release pattern with the value of r2 ˃ 0.99. Once-daily tablets released 98–100% drug in 24 h. Significantly more concentration and higher viscosity grade of hydrophilic polymer ensured the required pattern of drug release.

Ethyl cellulose particles loaded with α-tocopherol for inhibiting thermal oxidation of soybean oil

Most endogenous antioxidants degrade and lose efficiency during frying. The study aimed to inhibit thermal oxidation of soybean oil by fabricating α-tocopherol loaded particles with ethyl cellulose (EC) of different viscosity grades (M9, M70 and M200) via anti-solvent method. As the viscosity of ethyl cellulose increased, particle size decreased from micrometer to nanometer. Confocal laser scanning microscope confirmed successful encapsulation and uniform distribution of α-tocopherol in the loaded particles. Differential scanning calorimetry and thermogravimetric analysis demonstrated that loaded particles protected α-tocopherol from oxidation and degradation. Meanwhile, Fourier transformed infrared demonstrated that α-tocopherol interacted with EC through hydrogen bond and hydrophobic effects. With excellent dispersibility in soybean oil, loaded particles effectively inhibited thermal oxidation of soybean oil and loaded M200 nanoparticles was the most effective, which performed far better than tert-butylhydroquinone (TBHQ). Therefore, the nanoparticles offered a promising way to enhance oxidative stability of oils during thermal processing.

Synthesis and characterization of zeolite-like additive: An eco-efficient asphalt mix production strategy

The objective of this study was to synthesize and characterize zeolite-like materials by mixing sodium aluminate, tetraethyl ammonium hydroxide (TEAOH) solution, and montmorillonite K10 (MMT K10); the final synthesis combination was termed as STEAM. Two different molar ratios of STEAM materials were modified into powdery form by hydrothermal reaction under specific curing conditions, which were blended with a viscosity grade VG-30 base asphalt binder. Conventional consistency tests reported that STEAM-modified asphalts reduced mixing and compaction temperatures by around 5–6 °C when compared to VG-30. Based on advanced rheological characterization, the STEAM modified binders showed improved rut-resistance characteristics than VG-30 by reducing non-recoverable creep compliance and increasing recovery parameters. Furthermore, the physicochemical properties of raw MMT K10 and STEAM additives indicated that MMT K10 was characteristic of high negative surface charge and multimodal polydispersity, while synthesized STEAM additives exhibited monomodal polydispersity and typically comprised of nano-sized particles. The powder XRD results of STEAM materials indicated the crystalline framework to be in similarity with “zeolite X, (Na)”. Thermal analysis of STEAM additives illustrated the presence of a higher amount of physically adsorbed water by more than 1.5–2 times than that of raw MMT K10. Overall, it is envisioned that the STEAM-modified asphalt binders will help reduce fuel consumption during the production of asphalt mixtures and qualify to be eco-efficient sustainable materials.

Raman spectroscopy for the identification of differences in the composition of automobile lubricant oils related to SAE specifications and additives

This study employed Raman spectroscopy for the identification of spectral differences in automotive lubricant oils with different SAE specifications. Samples of 18 lubricant oils were obtained from a local auto parts store. Spectra were obtained with a dispersive Raman spectrometer (830 nm) and separated according to the type of base oil in the samples: mineral, semi-synthetic and synthetic. Also, samples were separated according to the SAE specifications regarding the viscosity grade in low and high temperatures. Principal component analysis (PCA) showed that the lubricants with mineral base oils presented peaks referred to aromatic hydrocarbons and additives containing aromatics, sulfites/dissulphites and sulfonates, while semi-synthetic and synthetic base oils presented peaks referred to alkanes. Other peaks referred to alkanes and olefins were also seen in synthetic base oils. The discriminant analysis based on quadratic distance applied to the PCA variables was able to discriminate the lubricant samples according to the type of base oil with 89.7% accuracy and discriminate the SAE viscosity grade for low and high temperatures with 95.8% and 90.0% accuracy, respectively. The use of Raman spectroscopy makes possible nondestructive evaluation of lubricant oils, which may replace expensive and complex traditional tests and methods of quality control.

Evaluation of Bituminous Mix Characteristics Prepared with Laboratory Developed High Modulus Asphalt Binder

Asphalt layers in India are widely constructed with the use of viscosity grade binder. The mixes prepared with this binder exhibit early distress because of uncontrolled heavy axle loads and high ambient temperature. Pavement engineering specialists are in search for improved performing pavement materials, more specifically on the top layer. As a matter of fact, the viscosity and stiffness of the asphalt binder play a critical role in the overall performance of pavements at elevated temperatures. The stiffer or hard binder shall provide solution for improving the performance. This article aims in evaluating the performance characteristics of high modulus asphalt concrete (HMAC) mixture from the laboratory-developed high modulus asphalt binder (HMAB). The HMAC mixes prepared with HMAB require a penetration value of 10/20 or 15/25 at 25 °C. The development of HMAB is assessed from the following laboratory tests (1) physical, (2) chemical and (3) rheological, while that of HMAC includes (1) Marshall properties, (2) tensile strength, (3) immersion-type rutting characteristics, and (4) resilient modulus tests. The developed HMAB has shown an increased performance grade (PG) of base binder from 64 to 76 °C. HMAC mix has shown remarkable resistance toward the permanent deformation than the base mix. Moreover, the resilient modulus of the HMAC was found to be improved by twice that of the base mix. Further, a pavement section model was designed for traffic of 300 msa, and the model performance was evaluated using IITPave and finite element analysis. HMAC pavement section was found to be more economical than pavement prepared with the base mix. The outcome of this study is expected to help pavement engineers and other agencies in the revision of guidelines for possible inclusion of polyphosphoric acid as an approved modifier for the production of HMAB.

Laboratory investigation of modified bitumen for interlayer in rigid–flexible composite pavement

Adhesion of composite pavement plays a significant role in the durability and maintenance of this type of pavement. The present research aims to assess the bonding and fatigue performance of rigid–flexible composite pavements through laboratory testing at different tack coat application rates. Three types of modified bitumen, crumb rubber-modified bitumen containing hydrated lime (CR/HL), crumb rubber-modified bitumen containing natural zeolite (CR/NZ), and crumb rubber-modified bitumen (CRMB), were selected as the tack coat. Shear fatigue and direct shear tests were utilized to assess the bonding properties of tack coats. The study also examines the behavior of modified bitumen by examining its viscosity, rheological properties, and performance grade. The results show that CR/NZ exhibits better performance in rheological behavior and at various temperatures compared to CR/HL and CRMB. Also, depending on the type of tack coat, shear strength tests show a range of 0.6–0.9 l m−2 as the optimal tack coat dosage. Finally, based on the optimal tack coat, shear strength ratings for various bitumen types may be classified as CRMB < CR/HL < CR/NZ.

Green preparation of branched biolubricant by chemically modifying waste cooking oil with lipase and ionic liquid

To reduce the environment pollution from biolubricant synthesis, in this study, we developed a green and efficient strategy for the preparation of octylated branched biolubricant from waste cooking oil (WCO): (1) WCO was first hydrolyzed by a lipase (Candida sp. 99–125) to produce unsaturated fatty acids (UFAs), the latter was subsequently concentrated by urea complexation; (2) Next, we synthesized new esters using the UFAs as substrate via esterification with 2-ethylhexanol employing lipase (Novozym 435) and the new esters products were further epoxidated; (3) After that, the epoxy group was attacked by a low-cost nucleophilic reagent, octanoic acid, to prepare octylated branched biolubricant using an recyclable ionic liquid, [HMIm][PF6], as catalyst. After three recycling times, [HMIm][PF6] remained catalytic activity with a conversion yield of 81.22% and selectivity of 82.10%. The obtained product showed excellent lubricant properties, such as low pour point of −61 °C, high viscosity index of 149 and high thermal-oxidation stability (onset temperature of 326.35 °C and oxidative onset temperature of 312.06 °C). The high frequency reciprocating rig (HFRR) measurement demonstrated that lubrication performance (friction coefficient of 0.09 and wear spot diameter of 203 μm) was much better than that of mineral based lubricant with the same viscosity grade. Therefore, this study provided a critical synthetic strategy for preparing high-performance biolubricants from WCO.

Experimental study on the oil return characteristics of miscible or partially miscible oil in R290 room air conditioners

R290 is a promising new refrigerant for room air conditioners because of its environmental friendliness and excellent thermophysical properties. It is necessary to lubricate the moving parts of compressors with oil. However, if a large amount of oil migrates into the heat exchanger from the compressor during system operation, the pressure drop will increase, and the heat transfer coefficient will decrease. There has been little research on the oil return in R290 air conditioners. In this study, the oil return characteristics of mineral oil (MO) with a relatively high viscosity grade and polyalkylene glycol (PAG) with an intermediate viscosity grade in an R290 room air conditioner were investigated using cold start-up, oil retention, and cyclic tests. The oil retention outside of the compressor in the steady state and the oil level and mixture viscosity of the oil sump in the compressor were measured. The results showed that the oil supply was adequate at the minimum oil level and that both the MO and PAG could return to the compressor within 35 min in the cold start-up tests. In addition, the oil retention in the system was 3.2–3.7 g for PAG and 3.5–8.2 g for MO in the steady state. The results suggested that both the R290/MO and R290/PAG systems exhibited good oil return.

Experimental investigation of low viscosity grade binder modified with Fischer Tropsch-Paraffin wax

The purpose of this study aims at investigating the effect of “Fischer Tropsch-Paraffin wax” (Sasobit) on the properties of low viscosity grade bitumen. Bitumen with viscosity grade-10 is selected as the control binder and later it is modified with different additive dosages of Sasobit (1–5%). Penetration, softening point and ductility tests were employed for evaluating the effect of Sasobit on basic physical properties of modified bitumen. A Dynamic Shear Rheometer (DSR) is also utilized for evaluating the rheological properties of the base and modified bitumen, for both aged and unaged bitumen. Based on the conventional and basic rheological tests, it was seen that the addition of Sasobit improved the high-temperature performance of modified bitumen and adversely affected the low-temperature performance at higher additive dosages greater than 1.5%. Therefore, the additive dosage has been optimized at 1.5% by weight of bitumen and thus the remaining tests have been carried out at 1.5% dosage. Multiple Stress Creep and Recovery (MSCR) test results revealed that the addition of wax improved the creep and recovery of modified binders for both stress intensities (0.1 kPa and 3.2 kPa) which confirms that the modified binder is more rut resistant. Also, the incorporation of Sasobit changed performance grade (PG) from 64 to 70. The isochronal and isothermal plots revealed that the Sasobit addition increases complex modulus. The increase is more prominent at higher frequencies. Thermal analysis has been performed by using thermogravimetry (TG) and results indicated that Sasobit delayed the initial decomposition temperature by 50°C and hence increased the thermal stability of modified binders. Also, Fourier Transform Infrared Spectroscopy (FTIR) is employed to study the effect of Sasobit on modified binders. It was observed that the addition of Sasobit did not alter the peaks. This specifies that asphalt and Sasobit have good miscibility and compatibility.

Experimental Investigation of the Viscosity Parameters Ranges—Case Study of Engine Oils in the Selected Viscosity Grade

The primary objective of the research was to compare the viscosity parameters of the same viscosity grade engine oils, as declared by the manufacturers, to the actual laboratory measurements. The secondary objective was to briefly investigate (1) what kind of information oil manufacturers provide in the product data sheets of the studied oils, and (2) the potential savings resulting from the use of the energy efficient oils. The study material consisted of 42 selected synthetic engine oils that belong to the 5W-30 viscosity grade. Stabinger SVM 3001 viscometer was used to determine kinematic viscosity at −20 °C, 40 °C, 100 °C and 130 °C. The HTHS (high temperature high shear), CCS (cold cranking simulator), FTIR (Fourier-transform infrared spectroscopy) and GC (Gas Chromatography) measurements were also performed for the samples that had the lowest and the highest kinematic viscosity. Large differences (5–25%) between oil producers’ declarations and the results of laboratory tests were found. Although all of the engine oils tested met the 5W-30 grade standards, the high variability of viscosity measurements needs to be reported. The difference between the oil with the highest and the oil with the lowest kinematic viscosity at −20 °C was 11,804 mm2/s. The outlying temperature-related viscosity profiles were recovered using Mahalanobis distances which identified 16 out of 42 analyzed oil samples as atypical.

Piribedil loaded thermo-responsive nasal in situ gelling system for enhanced delivery to the brain: formulation optimization, physical characterization, and in vitro and in vivo evaluation.

Methyl cellulose (MC) based nasal in situ gels were developed to enhance the brain delivery of piribedil (PBD), an anti-Parkinson's drug. Different grades of MC and several solutes (NaCl, KCl, Na.Citrate, STPP, PEG-6000, sucrose, etc.) were screened to formulate thermo-responsive nasal in situ gelling systems. Formulations were evaluated for their sol-gel transition temperature and time, rheological behaviour, in vitro drug release, mucociliary clearance (MCC), ex vivo nasal toxicity, and in vivo brain availability studies in Wistar rats. Intranasal (i.n.) administration was carried out using a cannula-microtip setup to deliver PBD at the olfactory region of the nose. The concentration and viscosity grade of MC and also the concentration and type of solute used were found to affect the rheological behaviour of the formulations. Among the solutes tested, NaCl was found to be effective for formulating MC in situ gels. The developed in situ gels significantly delayed the MCC of PBD from the site of administration when compared with conventional suspension (p < 0.05). Further, formulations with higher gel strength showed lower in vitro drug release rate and longer intranasal residence (delayed MCC) (p < 0.05). The absolute brain availability (brain AUC0-t) of PBD increased to 35.92% with i.n. delivery when compared to 4.71% with oral administration. Overall, it can be concluded that intranasal delivery of PBD is advantageous when compared to the currently practiced oral therapy. Graphical abstract.