Rejuvenation Agent Research Articles

Influence of combined aging on the mechanical and physical properties of reclaimed asphalt pavement mixtures blended with rejuvenator agents

Recently, reclaimed asphalt pavement (RAP) with high RAP contents with rejuvenator agents have been implemented in Japan. However, a unified view of the durability of RAP mixtures with rejuvenators has not been established. Therefore, this paper aims to assess the durability of RAP mixtures blended with different types of rejuvenators through combined aging, compared with that of hot mixed asphalt (HMA) mixture. Mechanical and physical properties of RAP mixtures with rejuvenators subjected to a combination of moisture, heat, and oxidation were investigated. Saturation aging tensile stiffness conditioning was used to simulate the combined aging. Four types of RAP mixtures were prepared by employing two types of oil-based rejuvenators with two RAP contents. HMA mixtures were also prepared. The test results demonstrated that the RAP mixtures did not exhibit a reduction in the retained stiffness, whereas the HMA mixtures exhibited a significant drop in stiffness with conditioning. In addition, the RAP mixtures exhibited a longer residual service life than the HMA mixtures after conditioning. Detailed analyses revealed differences in the stiffness and fatigue behaviors of the RAP mixtures with different types of rejuvenators. Finally, certain aspects of the deterioration mechanisms of RAP mixtures with rejuvenators were discussed.

Evaluation of Waste Tire Pyrolytic Oil as a Rejuvenation Agent for Unmodified, Polymer-Modified, and Rubber-Modified Aged Asphalt Binders

This study evaluated tire pyrolytic oil (TPO) derived from waste tire pyrolysis as a rejuvenating agent for three types of aged asphalt binders (unmodified, polymer-modified, and crumb rubber–modified). Gas chromatography–mass spectrometry (GC–MS) was performed to identify chemical compounds present in TPO. The rheological characteristics of all binders were examined through the complex viscosity–frequency profile, zero-shear viscosity, failure temperature, Black space diagrams, Cole–Cole plots, Superpave fatigue parameter, Glover–Rowe parameter, and linear amplitude sweep (LAS) tests. Mass loss was also determined for the rejuvenated binders. All binders were subjected to Fourier transform infrared (FTIR) analysis, and sulfoxide and carbonyl indices were computed. Atomic force microscopy (AFM) was conducted to study the effect of TPO on the micromorphology of the binders. The normalized Euclidean distance approach was used to rank the rejuvenated binders with respect to the proximity of their rheological and FTIR characteristics to that of the unaged binder. The use of TPO as a rejuvenating agent enabled the aged binders to achieve properties comparable to those of the unaged asphalt binder. The AFM-based rejuvenation index (RI) indicated a good potential of TPO as a rejuvenator. The results of the binder rheological parameters and the FTIR indicators investigated in the study indicated that a 9% dosage of TPO as a rejuvenating agent was the most effective.

Performance of waste plastic bio-oil as a rejuvenator for asphalt binder

Pavement recycling is actively applied on asphalt roads due to ageing problems associated with bituminous binders when exposed to weathering and trafficking during their service life. Recycling of asphalt occurs through rejuvenator agents. This study utilised bio-oil produced from hydrothermal liquefaction of waste plastic films (linear low-density polyethylene - LLDPE) to rejuvenate laboratory-aged bitumen. Initially, the neat bitumen was aged through thermal ageing (Pressure Ageing Vessel – PAV) and then the aged binder was mixed with bio-oil from waste plastics at 5% and 8% bio-oil (BO) by weight of aged binder. All four binders including neat bitumen, aged bitumen, aged bitumen/BO-5% and aged bitumen/BO-8% were analysed for thermogravimetric analysis, Fourier Transform Infra-Red analysis, rheology in the linear viscoelastic region, multiple stress creep and recovery analysis, and linear amplitude sweep analysis. The ageing of neat binder resulted in hardening of the binder; however, the bio-oil rejuvenator softened the aged binder significantly. The thermo-chemical and rheological performance of aged binder was significantly improved after the addition of bio-oil. The outcomes suggest how bio-oil produced from hydrothermal liquefaction of waste plastics (possibly non-recyclable) may serve as potential rejuvenator for aged asphalt binders in an effort to recycle more using non-recyclable material.

Assessment of Durability of Reclaimed Asphalt Pavement Mixtures Blended with Rejuvenator Agents Through Combined Aging

Assessment of Durability of Reclaimed Asphalt Pavement Mixtures Blended with Rejuvenator Agents Through Combined Aging

Quantitative assessment and mechanism analysis of modification approaches for cold recycled mixtures with asphalt emulsion

Cold recycled mixtures with asphalt emulsion (CRMEs) are environmentally friendly and cost-effective materials widely used in asphalt pavement maintenance and rehabilitation (M&R). However, CRMEs exhibit lower mechanical performance and durability than hot-mix asphalt. This study aims to evaluate the effects of different modification approaches on the mechanical properties and durability of CRMEs. To this end, four optimal additives, including the rejuvenation agent (RA), basalt fibres (BFs), styrene–butadiene rubber (SBR) latex, and Buton rock asphalt (BRA), were added to CRMEs during the mixing procedure. Comprehensive laboratory tests including immersion splitting and freeze–thaw splitting tests, high-temperature rutting tests, low-temperature semi-circle bending tests, and indirect tensile fatigue tests were conducted to evaluate the mechanical properties of the modified CRMEs. In addition, the radar chart method was performed to quantitatively assess the effects of the multiple modification approaches. To investigate the influence mechanisms, microscopic features of the modified CRMEs, such as the compactness of the mortar and bonding sufficiency of the interface, were detected by scanning electron microscopy. The results showed that the addition of RA, SBR latex, and BRA can improve the comprehensive performance of the modified CRMEs. Among these additives, RA had the most significant effect, followed by BRA. These findings aid in selecting modifiers to improve the performance and durability of CRMEs in practical engineering applications.

The Evaluation of Rationality of Medicines Use in Terms of Prescribing Indicators At The Health Center (Puskesmas) Serdang Bedagai District In 2019

Objective: The aim of this study was to determine the effectiveness of aloe vera gel in inhibiting skin aging.
 Method: The powder was extracted with ethanol in macerated method. Extract ethanol were analyzed for antioxidant activity with DPPH assay. Aloe vera extract that has been obtained then made variations of different extract concentrations namely 3% and 6% based on the orientation of researchers to determine the concentration, then in the formulation into gel. Anti-aging activity testing using skin analyzer tools with moisture parameters, collagen levels, pore, sensitivity before and after exposure to UV A and UV B rays.
 Results: IC50 value of aloe vera extract obtained by 138.65 ppm. Based on the classification of antioxidant activity shows that IC50 value of aloe vera extract has moderate antioxidants that range from 101 to 250 ppm. The percentage of moisture content in week I to week IV, F3 has an increase of 26% i.e week 1 is 4% and week IV is 30%. The percentage of collagen levels in week I to week IV, F3 has an increase of 50% i.e week 1 is 30% and week IV is 80%. Increase in the percentage of elasticity in the week I to week IV. F3 had the highest increase of 25%, in week 1 it was 50% and week IV was 75%. A large decrease in pores occurs in weeks I through week IV. F3 had the highest decrease of 0.06 mm, in the week I was 0.07 mm and week IV was 0.01 mm.
 Conclusion: Aloe vera extract gel preparation has activity as a rejuvenation agent at a concentration of 6%.

Potential Extract Ethanol of Aloe Vera Gel as a Rejuvination Agent

Objective: The aim of this study was to determine the effectiveness of aloe vera gel in inhibiting skin aging.
 Method: The powder was extracted with ethanol in macerated method. Extract ethanol were analyzed for antioxidant activity with DPPH assay. Aloe vera extract that has been obtained then made variations of different extract concentrations namely 3% and 6% based on the orientation of researchers to determine the concentration, then in the formulation into gel. Anti-aging activity testing using skin analyzer tools with moisture parameters, collagen levels, pore, sensitivity before and after exposure to UV A and UV B rays.
 Results: IC50 value of aloe vera extract obtained by 138.65 ppm. Based on the classification of antioxidant activity shows that IC50 value of aloe vera extract has moderate antioxidants that range from 101 to 250 ppm. The percentage of moisture content in week I to week IV, F3 has an increase of 26% i.e week 1 is 4% and week IV is 30%. The percentage of collagen levels in week I to week IV, F3 has an increase of 50% i.e week 1 is 30% and week IV is 80%. Increase in the percentage of elasticity in the week I to week IV. F3 had the highest increase of 25%, in week 1 it was 50% and week IV was 75%. A large decrease in pores occurs in weeks I through week IV. F3 had the highest decrease of 0.06 mm, in the week I was 0.07 mm and week IV was 0.01 mm.
 Conclusion: Aloe vera extract gel preparation has activity as a rejuvenation agent at a concentration of 6%.

Renovation the Physical Characteristics of Aged Bitumen Using Vacuum Residue

For most countries, the use of recycled asphalt pavement (RAP) has become increasingly common practice as it is both an environmentally and economically desirable option. The aging of bitumen throughout Stocking, blending, transporting and placement on Ways And even service life, the much more severe issues presented through the use of bitumen for pavements. This Research explores A potential of using vacuum residue oil as an effective Rejuvenation agent for aged bitumen, which is a by-product of a condition identical to the original bitumen. As the control binder, Bitumen with Pen 50-60 was selected. At different concentrations, vacuum residue oil was added0 percent, 2.5 percent, 5 percent, 7.5 percent and 10 percent respectively by weight of the total binder in aged bitumen at different concentrations Including penetration, softening point, penetration index ( PI), the features of the renewed bitumen have been tested. As the VR concentration increased Both binding time and temperature were strongly dependent on the ability to merge Of the aged ,Virgin Binders. Reduced mixing temps Decreased diffusion of virgin bitumen and aged binder.

Trends in Surgical and Beauty Masks for a Cleaner Environment

The surgical face mask (SFM) is a sheet medical device covering the mouth, nose and chin to protect the medical staff from the spread of respiratory droplets produced by the infective coughing or sneezing of hospitalized patients. On the other hand the beauty face mask (BFM) has been made by the same sheet but with a different aim—to protect the skin from pollution, acting as a hydrating and rejuvenation agent. Currently, both masks are made principally by non-biodegradable tissues, utilized to avoid the increasing great pollution invading our planet. Due to the diffusion of the current COVID-19 infection rate and the increasing consumption of skin care and beauty products, the waste of these masks, made principally by petrol-derived polymers, is creating further intolerable waste-invaded land and oceans. After an introduction to the aims, differences and market of the various masks, their productive means and ingredients are reported. These news are believed necessary to give the reader the working knowledge of these products, in the context of the bioeconomy, to better understand the innovative tissues proposed and realized by the biobased and biodegradable polymers. Thus, the possibility of producing biodegradable SFMs and BFMs, characterized for their effective antimicrobial and skin repairing activities or hydrating and antiaging activity, respectively. These innovative smart and biodegradable masks are requested from the majority of consumers oriented towards a future green environment. Giving this new sense of direction to their production and consumption, it will be possible to reduce the current waste, ranging worldwide at about 2 billion tons per year.

Vermicompost Leachate as a Promising Agent for Priming and Rejuvenation of Salt-Treated Germinating Seeds in Brassica Napus

ABSTRACTSalinity is a major constraint hampering germination and early seedling growth, especially in aged seed lots. Any rejuvenation treatment improving salt resistance at these crucial developmental stages will be of special interest. Two sets of experiments were performed in Brassica napus to precise the impact of vermicompost leachate (VCL) on seed germination in the presence of NaCl and to analyze its putative interest as seed priming agent before NaCl exposure. Two seed lots were used: one old seed lot (cv. Libomir) and a recent one (cv. Harry). VCL increased the germination percentage of aged seeds in the absence of NaCl and increased seedling length in both cultivars. VCL had only a minor impact when directly added to the NaCl-containing germinating solution. In contrast, priming with VCL strongly improved subsequent germination in the presence of NaCl in relation to a more efficient management of oxidative stress in both cultivars. The improvement of salinity resistance provided by VCL priming was not due to modification in ion or proline content. It is concluded that VCL may act as a rejuvenation agent invigoring old seed lots and as an efficient priming agent for improvement of salinity resistance at the germination stage. Valuable properties of VCL are discussed in relation to the simultaneous presence of several protecting compounds.

Asphalt mixtures with a high amount of RAP – case study

A case study of one trial section in the Pilsen region is presented. The pavement in the section was newly constructed in 2015 using one type of an asphalt concrete mixtures with varying RAP content. The constructed surface course comprises of 0% to 50% RAP. In order to restore the aged binder properties and to avoid the embrittlement of the produced mixtures, a rubber-based modifier/rejuvenator was employed. For technological reasons during manufacturing processes, which engage a parallel drying drum, a crude oil-based rejuvenator was also added. This article contains the preliminary data from an on-going project focused on monitoring the properties of bituminous binders contained in asphalt mixtures. The actual bituminous binders were extracted straight after production, after 6 months and after 12 months. The binder characteristics are evaluated using empirical testing as well as functional tests. Low temperature properties are measured by a Bending Beam Rheometer (BBR). The preliminary results show, that the bituminous binders properties change significantly in a relatively short period of time. The progress in binder’ characteristics is contradictory to up-to date knowledge. The probability that the phenomenon of diffusion between aged binder and rejuvenator agents occurs exists. Moreover, the data might indicate that the process of rejuvenator evaporation takes place.

Experimental study on the use of rejuvenators and plastomeric polymers for improving durability of high RAP content asphalt mixtures

The use of RAP (Reclaimed Asphalt Pavement) in new asphalt pavements could potentially generate environmental footprint reduction especially in terms of raw-material consumption. This investigation aims to evaluate the effectiveness of the addition of rejuvenator and plastomeric polymer on the performance of high RAP content (40%) asphalt mixture. Six combinations, varying proportion of rejuvenator and polymer, were studied. Mechanical and long-term performance was evaluated through laboratory investigations analyzing the physical properties and rheology of the binder and measuring stiffness modulus and permanent deformations (rutting) of recycled asphalt mixes.Outcomes showed that a proper calibration of rejuvenation agent and polymer can enhance the overall durability of high RAP content mixes. Statistical analysis of results was also conducted to determine the significance of variables involved.

Application of rejuvenators and virgin bitumen to restore physical and rheological properties of RAP binder

Both chemical and rheological aspects of aged bitumen in reclaimed asphalt pavement (RAP) material play an important role in the final performance of bituminous mixtures containing recycled asphalt material. This must be especially considered in the case of pavements containing high RAP content. The use of rejuvenators and/or virgin bitumen in recycled mixtures helps improving the properties of aged bitumen. This research study investigates RAP oxidised bitumen and its possible rejuvenation with virgin bitumen and addition of various additives as rejuvenator agents. Tests were conducted to analyse the chemical, rheological and physical behaviours of several binder mixes before and after laboratory ageing processes. Long-term ageing of rejuvenated binder mixes was also investigated to assess the effectiveness of rejuvenation over time. The results showed that the addition of virgin bitumen and rejuvenators could improve the performance of oxidised bitumen and increase its resistance to further ageing.

Rejuvenator Influence on Aged Binder Material Properties

As the amount of reclaimed asphalt pavement (RAP) material used in asphalt mixtures has increased recently, it is vital to address problems regarding aged binder incorporated in RAP. Asphalt binder hardens during its production process as well as during service life of pavements. External influences such as oxygen and ultraviolet radiation affect greatly bitumen characteristics. Thanks to adding rejuvenating agents, the original binder properties should be recovered and resulting asphalt binder parameters should become equal to those measured upon the reference material. In this study, four different rejuvenator agents and one neat soft binder were employed to rejuvenate the artificially aged binder by a complete blending between both constituents. Thereafter, empirical as well as performance based binder properties were examined with a dynamic shear rheometer (DSR) and with a bending beam rheometer (BBR). Three different dosages of each rejuvenator were added to evaluate the required amount for the original binder properties to be restored. Moreover, the softening efficiency of each agent was assessed by means of the Ring and Ball test. Finally, the optimum amount of each rejuvenator needed for the blend to achieve the target specification was determined. It can be concluded that the rejuvenators affect binder properties greatly, and mainly in a positive way. However, the data also indicate significant discrepancies between the types of the rejuvenator.

Investigation on the Chemical and Physical Properties of Vegetable Oil-Based Polyols for their Potential Application as Asphalt Rejuvenators

Up to date, no extravagant attempts have been made to use the vegetable oil-based polyols as rejuvenator agents for aged asphalts. In this context, the nature and composition of these biodegradable products need to be identified and physicochemical properties of different nature of compounds need to be measured. Three different vegetable oil-based polyols designed as castor oil polyol, soybean flexible polyol, and soybean rigid polyol were characterized by FT-IR, TLC-FID, 1H-NMR, and 13C-NMR and by the determination of some usual characteristics such as acid value, hydroxyl value, iodine value, and viscosity. It is speculated that the soybean flexible polyol may serve as a potential rejuvenator for aged asphalts.

English

Botulinum toxin type A is one of the most used products in mitigation of wrinkles and expression lines by promoting muscle paralysis. Because of their hydrophilic and high molecular mass, this active has low permeability through the skin. Thus, to exert its action as rejuvenation agent, botulinum toxin needs to be applied through intramuscular injections, causing pain and discomfort to the patient. An alternative to minimize this problem is encapsulation of the neuropeptide in nanocarriers that can easily cross the skin barrier. Thus, the aim of this work was to study the feasibility of encapsulation of botulinum toxin A in polymeric nanoparticles and liposomes. It was possible to demonstrate the formation of nanoparticles and liposomes loaded with botulinum toxin A. It was observed that liposomes containing botulinum toxin had an effect on neurotransmitters most effective in tests in vitro. The results demonstrate that it is possible to encapsulate botulinum toxin type A in liposome form without altering its biological action. Key words: Botulinum toxin type A, liposomes, nanoparticles.

A REVIEW ON APPLICATION OF WASTE COOKING OIL AS REJUVENATOR IN POROUS ASPHALT MIXTURE

Aging process of bitumen is one of the main obstacles, which limit the implementation of porous pavement. An aging process would cause a shorter service life of porous asphalt compared to the conventional hot mix asphalt mixture. The tendency rate of aging processes in porous asphalt is high due to the exposure of bitumen and aggregates binding in an open-graded structure that maximizes oxidation process to occur thus producing aged binder. In this respect to restore the original characteristics of pavement from aged bitumen, rejuvenation of bitumen binder offers an effective option. From the previous research, the performance of waste cooking oil (WCO) is investigated and indicated as one of rejuvenator agents for bitumen regeneration. Thus, this paper reviewed the novelty of the WCO, as an alternative natural rejuvenating agent for aged bitumen to a condition that resembles the original bitumen in the asphalt mixture.

Improving Recycled Asphalt Mix Performance Through Rejuvenation

Developing technologies that provide sustainable solutions for future pavement construction is vital given the ever-increasing demand on the supply of bitumen and good-quality pavement construction materials. Recycled asphalt pavement (RAP) is a technology that presents many advantages in cost and environmental savings. This study investigated the performance of RAP mixes containing rejuvenation additives to determine the effects of those additives on the deformation (rutting) resistance, cracking resistance, and fatigue performance of RAP mixes. Laboratory testing was conducted on 11 RAP mixes that were manufactured with RAP proportions of 15% and 30%, as well as with the addition of different types of rejuvenating agents. Results produced useful performance indicators for the use of rejuvenation additives in RAP. The mixes that had rejuvenation additives preserved the high deformation resistance of RAP mixes, particularly at the higher RAP proportion of 30% when compared with a mix with no RAP, and concurrently the addition of rejuvenators counteracted against overstiffening effects of RAP. The addition of RAP, especially 30% RAP proportion, had poorer fatigue performance than when only 15% RAP was used, but with the use of rejuvenation agents, the fatigue performance of the high RAP mixes improved significantly. Use of a maltene fraction for RAP rejuvenation had marginally better fatigue performance than a chemical rejuvenation agent. The research results provide a valuable understanding of the behavior of RAP mixes and, in particular, the positive performance results that can be gained by using rejuvenation additives.

Laboratory Study on the Effect of Asphalt Emulsion as a Rejuvenator in Aged Asphalt Pavement

Modification of the asphalt binder is one approach taken to improve aged pavement performance. To make the most of maintenance budgets, many agencies have resorted to the use of asphalt rejuvenators as an alternative to revive aging and brittle asphalt pavements. The purpose of this study is laboratory research on the effect of asphalt emulsion in restoring the original properties of aged asphalt pavement. For this purpose, the repeated load axial test is carried out on conventional asphalt samples and aged asphalt samples containing rejuvenator agents in different stress and rejuvenator percentage. Bitumen aged with RTFO according to ASTM-D2872 and the optimum bitumen of 5.5% were considered. The softening point and penetration tests, to examine the effect of rejuvenator in asphalt mixtures modification, On the basic, aged and modified aged bitumen were performed. The results represent that asphalt emulsion as a rejuvenator material in aged asphalt samples because of suitable performance improve aged asphalt permanent deformation resistance and aged bitumen Rheological property.

Are totally recycled hot mix asphalts a sustainable alternative for road paving?

The recycling of reclaimed asphalt pavement (RAP) helps road authorities to achieve their goal of a sustainable road transport system by reducing waste production and resources consumption. The environmental and economic benefits of using RAP in hot mix asphalt (HMA) applications could be pushed up to the limit, by producing totally recycled HMAs (100% RAP), but the performance of this alternative must be satisfactory. In fact, these mixtures could possibly present problems of workability and durability, higher binder aging and low fatigue cracking resistance. Thus, the objective of this study is to determine if totally recycled HMA mixtures could be a good solution for road paving, by evaluating the merit of some rejuvenator agents (commercial product; used engine oil) in improving the aged binders’ properties and the recycled mixture performance. Several binder samples were prepared with the mentioned rejuvenators and characterized (Pen, R&B and dynamic viscosity), in order to select the best rejuvenator contents. The production temperatures of the corresponding recycled mixtures were evaluated based on their workability. Totally recycled HMAs were produced with the best previously observed combinations, and their performance (water sensitivity, rutting resistance, stiffness, fatigue resistance, binder aging) was assessed. The main conclusion of this study is that totally recycled HMAs can be a good alternative for road paving, especially if rejuvenator agents are used to reduce their production temperature and to improve their performance.