Cellulose nanomaterials are promising materials for the polymer industry due to their abundance and renewability. In packaging applications, these materials may impart enhanced gas barrier performance due to their high crystallinity and polarity. In this work, low barrier to superior gas barrier pristine nanocellulose films were produced using a shear-coating technique to obtain a range of anisotropic films. Induction of anisotropy in a nanocellulose film can control the overall free volume of the system which effectively controls the gas diffusion path; hence, controlled anisotropy results in tunable barrier properties of the nanocellulose films. The highest anisotropy materials showed a maximum of 900-fold oxygen barrier improvement compared to the isotropic arrangement of nanocellulose film. The Bharadwaj model of nanocomposite permeability was modified for pure nanoparticles, and the CNC data were fitted with good agreement. Overall, the oxygen barrier performance of anisotropic nanocellulose films was 97 and 27 times better than traditional barrier materials such as biaxially oriented poly(ethylene terephthalate) (BoPET) and ethylene vinyl alcohol copolymer (EVOH), respectively, and thus could be utilized for oxygen-sensitive packaging applications.

No abstract

Nanocellulose has potential as a reinforcing agent to improve stiffness and strength in polymer fiber; however, the inherent difference in hydrophilicity makes it challenging to incorporate it into nonhydrophilic polymers, and the composite properties are strongly anisotropic. In the present work, a dual approach was employed to incorporate cellulose nanofibrils (CNFs) into polylactic acid (PLA). Polyethylene glycol (PEG) acted as a compatibilizating agent to enable the melt spinning of CNF/PLA composite fibers without water/solvent, and CNFs were surface modified to improve compatibility, increase nanoparticle thermal stability, and increase CNF dispersion in PLA. While no significant difference was observed in strength, the stiffness improved up to 600% (1.3 wt % CNF, maximum draw) in the composite fibers. This improvement was correlated with the crystallinity and fiber orientation (Herman's order parameter) for as-spun and hot-drawn fibers.

Hunger and chronic undernourishment impact over 800 million people, which translates to ≈10.7% of the world's population. While countries are increasingly making efforts to reduce poverty and hunger by pursuing sustainable energy and agricultural practices, a third of the food produced around the globe still is wasted and never consumed. Reducing food shortages is vital in this effort and is often addressed by the development of genetically modified produce or chemical additives and inedible coatings, which create additional health and environmental concerns. Herein, a multifunctional bio‐nanocomposite comprised largely of egg‐derived polymers and cellulose nanomaterials as a conformal coating onto fresh produce that slows down food decay by retarding ripening, dehydration, and microbial invasion is reported. The coating is edible, washable, and made from readily available inexpensive or waste materials, which makes it a promising economic alternative to commercially available fruit coatings and a solution to combat food wastage that is rampant in the world.

Since its relatively recent independence in 1971, a total of seven national Education Commissions were formed, all of which placed various degrees of emphasis on the planning, pedagogy and learning of English in Bangladesh. Although the first Education Commission in 1974 aimed to 'decolonise' the education system and effectively exile English from the country, English has always remained a top priority in the school curriculum. Studies have linked this to residual colonial legacy inherited from the British education system. In the backdrop of persistent nationalistic favouritism towards Bengali, English is still widely an area-specific language confined to academia, and English education is often still seen as a purely instrumentalist endeavour. However it is also important as a symbol of socio-intellectual elitism and prestige. Such mixed, often incongruous positions can be seen reflected in the way successive National Education Policies have interacted with Commissions, which some critics have pointed out were formed by various regimes to advance their political agenda and ideology rather than to further the country's pragmatic needs and achieve well-articulated and time-sensitive policy outcomes. This article critically reviews the major trends of English education policy as enacted through four decades of reform and how English has played out in the education system in a developing country fast emerging as a rich ground of alternative educational research. Through a brief chronology of education policy and commissions and drawing on the comparative shifts of emphasis on English through their recommendations over a period of four decades, the article situates the place of English within the pragmatics of a postcolonial mindset and the socio-cultural expectations of stakeholders, and deals with the complexities of transition from policy to practice. In particular it problematises the almost irreconcilable friction between English and Bengali forged through the nationalistic sentiment born in the Language Movement of 1952, an episode unique in the history of the world. Rather than looking into the politics of policy planning and implementation, it looks towards the possibility of an education system that can bring about a healthy juxtaposition between heritage and modernity.