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Ionic liquid is increasingly being used as a chemical modulator of multi‐walled carbon nanotubes (MWCNT). Here, we report the practical method for producing biodegradable electromagnetic interference (EMI) shield films made of thermoplastic polyurethane (TPU), polybutylene adipate‐co‐terephthalate (PBAT), and 1‐(2‐aminoethyl)‐3‐methyl‐1H‐imidazol‐3‐ium modified MWCNT (MIL). The field emission scanning electron microscopy study of cryo‐fractured 50:50 PBAT/TPU blend giving co‐continuous morphology and subsequent polymer EMI shield nanocomposite material had shown the co‐continuous nanofiller distribution. The nanoparticles were chosen to be distributed in the PBAT portion, according to subsequent research employing HRTEM and DMA. The electrical percolation threshold (EPT) is determined to be situated within 1–3 wt% of nanoparticles loading as the remarkable shift in total EMI shielding efficiency from −14.6 dB (for 1 wt%) to −28.6 dB (for 3 wt%) of nanoparticle‐loaded film at 10 GHz (in X‐band region) for a 0.8 mm thick film reveals that the EPT is approximately at 2 wt% of nanoparticle loading. The effective EMI shielding of −37.3 dB was achieved by 10 wt% of MIL loading. [ABSTRACT FROM AUTHOR]

Multifunctional polymer/graphene based lightweight and flexible nanocomposite films are increasingly being utilized in the packaging, electronics, and pharmaceutical industries together. Herein, two graphene derivatives: silver nanoparticle decorated reduced graphene oxide (G‐Ag) and chemically reduced graphene oxide (rGO) prepared by wet chemical method and graphene nanoplatelets (GNP) have been incorporated into linear low density polyethylene (LLDPE) thermoplastic matrix via melt compounding method. The incorporation of graphene derivatives affected the physico‐mechanical, electrical and thermal conductivity, and barrier properties (both oxygen and water vapor permeability) of the nanocomposite films. With 5 wt% of G‐Ag, rGO, and GNP loading, the thermal conductivity of these three nanocomposite films was enhanced by an average of 136.7%, 123%, and 143.3%, respectively. Graphene having high specific surface area and aspect ratio allow for a tortuous passage of oxygen and water molecules through the nanocomposite film, ultimately improving both oxygen and water vapor impermeability qualities for all LG‐Ag, LrGO, and LGNP nanocomposites. Moreover, the films have been tested against both gram‐positive and gram‐negative bacteria to ensure their bactericidal activity. The prepared composite films also showed Electromagnetic Interference (EMI) shielding effectiveness (−21, −17, and −19 dB) higher than the commercial cut‐offs. The thermoplastic nanocomposite films with promising thermal conductivity might be an excellent choice for bacteria‐resistant and barrier‐capable packaging and efficient thermal management EMI shields in electronics. [ABSTRACT FROM AUTHOR]

Flexible and electrically conductive polymer nanocomposite materials are gaining popularity as EMI shield materials. Herein, we report the successful fabrication of Thermoplastic polyurethane (TPU)/polybutylene adipate‐co‐terephthalate (PBAT)/dodecyl amine modified multi‐walled carbon nanotubes (MWCNT)‐based biodegradable polymer nanocomposite films employing solvent mixing and casting technique. The FESEM analysis of the cryofractured TPU/PBAT blend (containing 50 wt% of both the polymers) is found to be perfectly co‐continuous. Field emission scanning electron microscopy (FESEM), High‐resolution transmission electron microscopy (HRTEM) analysis followed by a selective dissolution test of polymer nanocomposites revealed that MAm nanofillers are mostly confined to the PBAT phase. The electrical percolation threshold is found to be between 3 and 5 wt% of dodecyl amine modified MWCNT loading as the electrical conductivity and EMI shielding efficiency are found to be shifting from 10−4 to 0.827 S/cm and −29.4 and −36 dB respectively as the nanofiller loading is increased from 3 to 5 wt% keeping the thickness of the polymer nanocomposite films constant at 0.8 mm. [ABSTRACT FROM AUTHOR]

Interference of electromagnetic (EM) radiation generated from different electronic gadgets produces noises diminishing their performance. So, shielding of EM interferences (EMI) is necessary to achieve noise‐free performance from electronic gadgets. In the present work, we have produced thermoplastic polyurethane (TPU)/polybutylene adipate‐co‐terephthalate (PBAT) based biodegradable binary polymeric blend and incorporated different carbonic nanofillers such as Vulcan XC‐72 conductive carbon black (VCB) and multiwalled carbon nanotube (MWCNT) into it employing solvent mixing and casting technique and studied the morphology of polymer blends, EMI shielding effectiveness in X‐band of the EM spectrum as well as mechanical performance, electrical performance, and biodegradability of polymer nanocomposites. The selective nanofiller distribution in the low viscous PBAT phase of the "co‐continuous" binary blend is found to achieve a "lower electrical percolation threshold" compared to neat polymer nanocomposites. For each of the TPU/PBAT/VCB and TPU/PBAT/MWCNT nanocomposites, electrical percolation threshold of around 12.5 and 5 wt% respectively has been achieved successfully. Nanocomposite sheets with a thickness of 1.0 mm and loading of 30 wt% of VCB and 15 wt% of MWCNT gave EMI shielding values of −25 dB and −28 dB respectively at a frequency of 8.4 GHz. [ABSTRACT FROM AUTHOR]

Harmful electromagnetic radiations that are generated from different electronic devices could be absorbed by a light weight and mechanically flexible good electromagnetic interference (EMI) shielding polymer nanocomposite. On the other hand, different electronic wastes ("e‐wastes") which are generally polymer building materials generated from wastes of dysfunctional electronic devices are not naturally biodegradable. Our recent effort has been employed to produce bio‐degradable EMI shielding polymer nanocomposite. For that purpose, we had prepared a 50:50 ratio polylactic acid/thermoplastic polyurethane polymer nanocomposite by mixing the conducting carbon black with the blend following the facile and industrially feasible solution mixing method. Morphological characterizations by scanning electron microscopy and transmission electron microscopy analysis revealed the co‐continuous morphology of the neat blend as well as polymer nanocomposites with the preferential distribution of conductive filler on a particular polymer phase. The polymer nanocomposites gave good mechanically with improved thermal properties. We got EMI shielding effectiveness around −27 dB with a low percolation threshold at around 30 wt% filler loading in the polymer nanocomposite at the X‐band frequency domain (8.2–12.4 GHz). Later we had studied the biodegradability of the PLA/TPU along with their composites (TXPXCX) by employing the respirometry method and got a satisfactory result to ensure their biodegradability. [ABSTRACT FROM AUTHOR]

Electrically conducting flexible polymeric nanocomposite has been fabricated through wet mixing method where conducting inclusion was acoustically exfoliated pristine graphene nanosheets. Colloidal graphene is the key component here which has been prepared by acoustic cavitation in the presence of macromolecular dispersion. The significance of the method is their green preparation strategy without using any chemical reducing agents and long self-life without drastic sedimentation rate. Thermoplastic poly(ethylene-co-methyl acrylate) was chosen as flexible phase where graphene sheets were distributed to make spatial conducting network architecture. The prepared nanocomposites showed 0.259 S/cm DC electrical conductivity and frequency-independent electroconducting character in higher concentration. The electromagnetic interference shielding effectiveness of the nanocomposites was around 30 dB in ~ 1.0 mm thickness in X-band (8.2–12.4 GHz) frequency range without affecting its mechanical toughness and flexibility. Thus, such pristine graphene-based thermoplastic matrix could be a desirable replacement of metallic shielding materials on the ground of flexible, conducting, lightweight characteristics. [ABSTRACT FROM AUTHOR]

To minimize radiation pollution at ultra‐low filler concentrations, there is a growing interest in microwave‐absorbing materials based on polymer blends composites. Herein, ethylene‐co‐methyl acrylate (EMA)/thermoplastic polyolefin (TPO) blend composites were prepared by employing solution mixing utilizing conductive Vulcan XC 72 carbon black (VCB) as nanofiller. The work focused on the reduction of electrical percolation and outstanding electromagnetic interference (EMI) shielding performance in low loading caused by the preferential distribution of carbon particles in one phase (ethylene‐co‐methyl acrylate copolymer) of the co‐continuous immiscible polymer blend. The fabricated conductive blend was further tested to ensure its superiority in physic‐mechanical and thermal stability. The morphology analysis reveals that the VCB particles are selectively localized in EMA phase of the blend which facilitates the formation of compact spatial conductive network throughout the matrix for electronic hopping. High electrical conductivity is achieved in the scale 10−2 S/cm for the prepared composites with 30 wt% of carbon black loading whereas a total EMI shielding effectiveness of −29 dB and thermal conductivity of ~0.75 W/m·K are achieved for this same filler content. This study reveals that the fabricated conductive polymer nanocomposites can be effectively utilized as promising EMI shields in the future generation of stretchable and wearable electronics. [ABSTRACT FROM AUTHOR]

Harmful disruptions are a result of the miniaturization and enhancement of contemporary electronics and communication. Self-healable, flexible, and lightweight elastomeric electromagnetic (EM) wave absorbers have replaced metal-based EM wave reflectors as state-of-the-art. Intending to boost the elastomeric nanocomposites' several functions, Herein, we prepared self-healable, flexible, and lightweight ZnO-XNBR/RGO nanocomposites with excellent thermal management and EMI shielding performance. A 1 mm thick nanocomposites film with DC electrical conductivity of 0.02 S/cm, thermal conductivity of 0.75 W/mK, a self-healing capability of 54.7%, 100% recyclability, excellent flexibility, and mechanical performance has been recorded with an EMI SE of − 34.2 dB in the X-band (8.2–12.4 GHz). Additionally, the uninterrupted conductive network remains unharmed by recycling, expanding, flexing, prolonged exposure to natural light, as well as chemical treatment, justifying its overall mechanical and chemical performance. These extended distortions exhibit greater than 90% retention of their shielding effectiveness (SE). In combination, the properties of our diversified elastomeric nanocomposites, including their superior shielding capability, self-healing capability, thermal management, recycling ability, and outstanding mechanical performance, provide an important guideline for developing robust elastomeric nanocomposites. [Display omitted] [ABSTRACT FROM AUTHOR]