Microcapsulation of phase change materials (PCMs) within a shell is one of the most feasible methods to explore their applications for thermal energy storage. Here, a facile method to microencapsulate PCMs within polystyrene/cellulose nanocrystal (CNC) hybrid shell via Pickering emulsion polymerization was developed. CNCs, as biobased and sustainable materials hydrolyzed from wood pulp, were employed as emulsifiers of the PCM Pickering emulsion and shell components of the PCM microcapsules as well. CNCs displayed a high efficiency in the stabilization of paraffin wax (PW) Pickering emulsion, and the heat capacity and stability of PW microcapsules with CNC shell (PW@CNC) increased dramatically with the amounts of CNCs. PW microcapsules with polystyrene and CNC hybrid shell (PW@PS/CNC) were prepared via Pickering emulsion polymerization of styrene from the CNC stabilized PW Pickering emulsion droplets. The PW@PS/CNC slurries possessed a latent heat capacity of 31.9 J/g with stability as high as 99.4% after 100 heating and cooling scans. The PW@PS/CNC powder possessed a latent heat capacity of 160.3 J/g, corresponding to a high encapsulation ratio of 83.5%. Moreover, coconut oil (CO), as an example of biobased PCMs, was also microencapsulated within polystyrene and CNC hybrid shell (CO@PS/CNC) via a similar method. Both PW@PS/CNC and CO@PS/CNC slurries displayed excellent temperature regulation ability and offered promising potentials for thermal energy storage systems.

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In today's world, transportation infrastructure plays a vital role in global competitiveness and quality of life in societies. The pavement industry deals with tremendous amounts of construction materials. Thus, even a small improvement in the technology can lead to significant environmental benefits and a reduction in the life‐cycle cost of road networks. Asphalt cement is an integral part of road pavement construction, and despite favorable properties at the processing temperature, some challenges need to be addressed to reduce cost and improve performance. This review discusses the nanocellulose modification of asphalt cement for pavement application. Three primary cellulose‐based nanoparticles were studied, including bacterial cellulose, cellulose nanofibers, and cellulose nanocrystals, and their applications in asphalt cement modification. Various research results show significant improvement in pavement's rheological and performance properties with the help of cellulose‐based nanoparticles. However, this review provides the reader with an objective evaluation of the benefits and practical challenges ahead of the industrial‐scale application of nanocellulose in the pavement industry.

A literature review was conducted on the main aspects of asphalt binder extraction and recovery: i) extraction methods, ii) recovery methods and iii) solvents. The extraction methods include centrifuge, reflux and vacuum and others with particular focus on their effectiveness in dissolving the binder and the potential to modify it. Studies found that the centrifuge was a relatively safe cold extraction method that was fairly effective. For the recovery methods, the rotary evaporator was found to have a good reputation for relative ease of use and less binder modification than for the Abson method. The most commonly used solvents n-propyl bromide and chlorinated solvents, while being reusable, both had reported issues of ineffectiveness as well as major concerns about user safety. Bio-sourced solvents were found to be seldom used and required higher quantities. The study concluded that more research needed to be done in developing solvents.

Emulsifier design is one of the key strategies in interfacial engineering for emulsion stability. In this study, cellulose nanocrystals (CNCs) were used as an interfacial stabilizer to improve the stability of coconut oil (CO)-in-water emulsions. A Pickering emulsion consisting of CO and water was optimized based on four parameters using the response surface methodology and the central composite design. The droplet coverage remained stable during the crystallization of the oil phase when the temperature was reduced below the melting temperature of CO. Fluorescent-labeled CNCs were used to monitor the partitioning of CNC at the O/W interface during the crystallization of CO. The Generation 6 polyamidoamine (G6 PAMAM) dendrimer covalently grafted on the surface of CNC was used as an intrinsic fluorescent dye. Since it displayed similar properties as the emulsifier, it could be used to monitor the CNC coverage on the oil droplets at various temperatures. The fluorescence micrographs showed that the emission of PAMAM CNCs at the O/W interface remained on both the liquid and solid CO droplets, confirming that oil crystallization did not affect the fluorescent CNC coverage on the oil droplets.