The development of new adhesives has allowed to expand the application bonding into most diverse industrial fields. This review article presents commonly used experimental methods for investigation mechanical performance adhesively bonded joints in aerospace, wind energy, automotive and civil engineering sectors. In these sectors, due their excellent intrinsic properties, composite materials are often along with conventional such as steel, concrete aluminium. this context, limitations that...

The versatile nature of photo‐induced thiol‐ene chemistry has made it one the most popular reactions in design polymer networks. In present work, structure uniform and complex binary thiol‐acrylate networks are studied detail by photopolymerizing cycloaliphatic linear alkyl thiols with an allyl monomer its acrylic counterpart. Along crosslink kinetics, balance between step growth chain mechanism two different systems is investigated FT‐IR spectroscopy. Low field NMR experiments carried out...

Abstract Conventional frontal polymerization processes for epoxy-based composites rely on cations and radicals generated by a short (and local) light or heat stimulus in the presence of an iodonium salt radical thermal initiator. However, due to losses, propagation exothermic curing front is often limited sample geometry filler concentration. Redox cationic (RCFP) promising approach radically expand composition design options frontally cured composites. By adding stannous octoate as reducing...

Selective laser sintering (SLS) is an additive manufacturing process which nowadays receives abundant attention from industry sectors. However, the number of materials can be processed by SLS still very limited and requires further research. The present work aims to contribute this topic investigating mechanical properties neat short carbon fibre reinforced polyamide 1212 SLS. specimens were built in different spatial alignments obtain ample details on tensile behaviour. detailed...

Frontal polymerization of epoxy-based thermosets is a promising curing technique for the production carbon fiber reinforced composites (CFRCs). It exploits exothermicity reactions to convert liquid monomers solid 3D network. A self-sustaining reaction triggered by heat or UV-radiation, resulting in localized thermal zone that propagates through resin formulation. To date, frontal limited CFRCs with low volume percent as losses compromise on propagation front, which crucial this autocatalytic...

Ionic liquids with selected anions (Tf2N–, BF4–, and PF6–) imidazolium cations bearing two terminal epoxy groups varying aliphatic, aromatic, dicationic spacers were synthesized. The synthesis procedures followed ion exchange mechanisms afforded the products in high yields. Vitrimers prepared by curing resins dodecenyl succinic anhydride presence of a base catalyst. In comprehensive approach, influence structure on cure kinetics, bond reactions, thermal, mechanical, healing performance...

Automated tape placement with in-situ consolidation (ATPisc) is a layer-wise manufacturing process in which the achievement of proper interlayer bonding constitutes one most challenging aspects. In present study, unidirectional carbon fiber reinforced thermoplastic laminates were produced following different protocols using ATPisc. The was characterized by mode I fatigue fracture tests double cantilever beam (DCB) specimens. Independent approach, exhibited multiple cracking during DCB...

Abstract Reversible adhesives are crucial for a circular economy of composites as they play key role rework, repair, and recycling adhesively bonded components. Herein, electrically debondable prepared by introducing ionic liquids in dynamic thiol–epoxy networks. The function the liquid networks is threefold it accelerates curing reaction between thiol epoxy monomers, facilitates electrical debonding, catalyzes thermoactivated transesterification reactions, required rebonding at elevated...

Abstract Radical induced cationic frontal polymerization (RICFP) is a promising route to achieve rapid curing of epoxy‐based thermosets, requiring only localized exposure with UV light. In the presence diaryliodonium‐based photoinitiator and thermal radical initiator, self‐sustaining hot front cures epoxide monomer via mechanism. However, diglycidyl ether derivatives slow (in comparison other epoxides higher reactivity) and, as consequence, sluggish because heat loss not compensated by rate...

The present study is devoted to the quantitative characterisation of interlayer bonding in unidirectional carbon fibre reinforced thermoplastic laminates produced by automated tape placement with in-situ consolidation (ATPisc). Two different manufacturing protocols were applied produce that further characterised using quasi-static mode I double cantilever beam (DCB) test. Regardless approach, exhibited multiple cracking accompanied bridging during testing, which affected main mid-plane crack...

This work explores the impact of hygrothermal aging on structural changes and tensile properties specimens from short carbon fiber reinforced PA6 matrix with without continuous reinforcement, manufactured using fused filament fabrication (FFF). The study reveals that environmental factors like humidity can affect material polymer composites, causing a hygroscopic swelling which leads to specimen warpage ultimately, reduction in strength. For this purpose, test were produced conditioned by at...

Dynamic polymer networks combine the noteworthy (thermo)mechanical features of thermosets with processability thermoplastics. They rely on externally triggered bond exchange reactions, which induce topological rearrangements and, at a sufficiently high rate, macroscopic reflow network. Due to this controlled change in viscosity, dynamic polymers are repairable, malleable, and reprocessable. Herein, several polyurethane were synthetized as model compounds, able undergo thermo-activated...

Abstract The tensile behavior of a flexible epoxy resin reinforced with knitted reinforcements from various fiber materials was comprehensively studied in the wale and course direction. By measuring dry yarns, temperature‐treated fabrics composites, effect material fabric on properties analyzed. interlock knit structure strongly affected deformation composites which differed significantly fabrics. monitored using digital image correlation revealed formation cracks high local strain...

ABSTRACT Repair of composite structures and the impact demanding environmental conditions is a crucial issue for aircraft industry because increasing use composites in modern aircraft. Consequently, common applications on repair specimens comparison to nonrepaired studied. All are produced from woven carbon fiber‐reinforced epoxy‐based prepreg. For repair‐specimens, an film adhesive used soft patch approach. During process, surface precured prepreg prepared by mechanical method (sanding)...

Poly(ionic liquids) (PILs) and ionenes are polymers containing ionic groups in their repeating units. The unique properties of these render them as interesting candidates for a variety applications, such gas separation membranes polyelectrolytes. Due to the vast number possible structures, numerous synthesis protocols produce monomers with different functional task-specific PILs reported literature. A difunctional epoxy-IL resin was synthesized cured multifunctional amine anhydride hardeners...

o accurately simulate the foam core in composite parts on a macroscopic scale morphology, characterisation, and nonlinear behaviour of thefoam must be understood properly. Accounting for heterogeneity mechanical properties affects dimensioning final part.In present study microstructure samples were characterized using scanning electron microscopy. To determine bulk material behavior strength limitations foam, shear compressions tests are performed. All numerical calculations carried out...