In this work, the mechanical and the self-healing behaviors of an ethylene-co-methacrylic acid ionomer were investigated in different testing conditions. The self-healing capability was explored by ballistic impact tests at low-velocity, midvelocity, and hypervelocity bullet speed; different experimental conditions such as sample thickness and bullet diameter were examined; in all impact tests, spherical projectiles were used. These experiments, in particular those at low and midspeed, allowed to define a critical ratio between sample thickness and bullet diameter below which full repair was not observed. After ballistic damage, the healing efficiency was evaluated by applying a pressure gradient through tested samples. Subsequently, morphology analysis of the affected areas was made observing all tested samples by scanning electron microscope. This analysis revealed different characteristic features of the damaged zones affected at different projectile speed. Stress–strain curves in uniaxial tension performed at different temperatures and strain rates revealed yield strength and postyield behavior significantly affected by these two parameters. A rise of temperature during high strain rate tests in the viscoplastic deformation region was also detected. This behavior has a strong influence on the self-repair-ing mechanism exhibited by the studied material during high-energy impact tests

In this research work, biocomposites based on a ternary system containing softwood Kraft lignin (Indulin AT), poly-L-lactic acid (PLLA) and polyethylene glycol (PEG) have been developed. Two binary systems based on PLLA/PEG and PLLA/lignin have also been studied to understand the role of plasticizer (i.e., PEG) and filler (i.e., lignin) on the overall physicomechanical behavior of PLLA. All samples have been prepared by melt-blending. A novel approach has also been introduced to improve the compatibility between PLLA and PEG by using a transesterification catalyst under reactive-mixing conditions. In PEG plasticized PLLA flexibility increases with increasing content of PEG and no significant effect of the molecular weight of PEG on the flexibility of PLLA has been observed. Differential scanning calorimetry and size-exclusion chromatography along with FTIR analysis show the formation of PLLA-b-PEG copolymer for high temperature processed PLLA/PEG systems. On the other hand, binary systems containing lignin show higher stiffness than PLLA/PEG system and good adhesion between the particles and the matrix has been observed by scanning electron microscopy. However, a concomitant good balance in stiffness introduced by the lignin particles and flexibility introduced by PEG has been observed in the ternary systems. This study also showed that high temperature reactive melt-blending of PLLA/PEG leads to the formation of a segmented PLLA-b-PEG block copolymer

The development of self‐healing materials, based on polymer blends, is an important issue either from a scientific or a technological point of view. The application of such materials can be remarkably extended if healing effects can be maintained even in polymers that are modified in order to tune their physical and mechanical behavior. In this research the self‐healing behavior of blends made of ionomers (sodium and zinc salts of poly(ethyelene‐co‐methacrylic acid)—EMNa and EMZn) with functionalized elastomers (epoxidized natural rubber with different epoxidation levels—ENR50 and ENR25, polyisoprene—PISP) of different compositions is investigated. The role of processing conditions, phase morphology, functionalization level, polymers compatibility over self‐healing response are discussed. Rubber functionality and phase dispersion are recognized as crucial factors affecting the healing efficiency of blends. Results of ballistic tests, DSC thermal analysis, FTIR spectroscopy, optical and electron (SEM and TEM) microscopy observations, rheological and mechanical tests are presented as supporting evidences.

The recent influx of Myanmar Rohingya people are allowed in Bangladesh simply due to humanitarian reason, of which older people are amongst the most vulnerable groups. Utilizing integrated methods, the refugee crisis is being managed jointly by various stakeholders. Young Power in Social Action (YPSA) is an NGO that has been providing support to older Rohingya people in the camps since the crisis began through their Age Friendly Support (AFS) centres.These centres provide basic medical treatment, counselling, education, health and wellbeing services, indoor games, and recreational services/activities. Yet, there have not been any studies to understand the expectations of older Rohingya people living in the camps. Thus, the purpose of this paper is to examine the current YPSA support for older Rohingya people living in the Ukhiya camps and to evaluate their expectations for returning to Myanmar. A pilot survey was conducted on 26 th April 2019 in two camp sites and in-depth interviews were also conducted with 4 participants (2 males and 2 females), followed by a focus group discussion.It emerged that older Rohingya people received necessary support services from these YPSA centres and are generally happy with those services. Although they remain grateful to Bangladesh for sheltering them, they are not as happy compared to their lives back in Myanmar.Most of the older people reported that their expectations involved a return to Myanmar as soon as possible as well as seeking justice from the international community so that the Rohingya crisis could soon come to an end.