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Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles

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A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Materials Simulation and Design".

Deadline for manuscript submissions: closed (10 February 2023) | Viewed by 32123

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Special Issue Editors

Prof. Dr. Dariusz Fydrych

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Guest Editor

Faculty of Mechanical Engineering, Gdańsk University of Technology, G. Narutowicza 11/12, 80-233 Gdańsk, Poland
Interests: underwater welding; mechanics of materials; testing of welded joints
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Prof. Dr. Andrzej Kubit

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Department of Manufacturing and Production Engineering, Faculty of Mechanical Engineering and Aeronautics, Rzeszow University of Technology, Al. Powst. Warszawy 8, 35-959 Rzeszów, Poland
Interests: refill friction stir spot welding; friction stir welding; thin-walled structures; adhesive joining; fatigue analysis of joints; composites; incremental sheet forming
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Prof. Dr. Ján Slota

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Institute of Technology and Material Engineering, Faculty of Mechanical Engineering, Technical University of Košice, 04001 Košice, Slovakia
Interests: modelling and simulation of sheet metal forming processes
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Dr. Agnieszka Kowalczyk

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Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology, 70-310 Szczecin, Poland
Interests: adhesives; photopolymerization; telomerization; acrylic resins
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Special Issue Information

Dear Colleagues,

The development of transportation vehicles must be related to ensuring the reduction of CO₂ emissions generated in land, air, and sea transport. In addition to the development of alternative energy sources and drive systems, it is necessary to develop load-bearing structures characterized by low weight, while ensuring the required strength and durability. In the structure of transportation vehicles (i.e., airplanes, cars, or ships), stiffened thin-walled structures are commonly used. Due to the need to search for new technological and design solutions, the research and development of new technologies of forming and joining thin-walled load-bearing structures are strongly desired by the industry.

Therefore, this Special Issue will publish high-quality scientific publications, especially those describing experimental research and numerical modeling of the technology of lightweight load-bearing structures. The main topics of the publications are welded joints of unweldable metals, adhesive joints, friction-welded joints, improvement of the impact strength and fatigue life of joints occurring in thin-walled structures, new methods of forming of stiffeners (e.g., incremental sheet forming), as well as sealing joints and their anti-corrosion protection. The aforementioned research topics should relate to the construction of vehicles, and the primary research objective should be to indicate the directions of new manufacturing methods that can reduce the weight of structures while maintaining their functional properties.

Prof. Dr. Dariusz Fydrych
Prof. Dr. Andrzej Kubit
Prof. Dr. Ján Slota
Prof. Dr. Agnieszka Kowalczyk
Guest Editors

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

thin-walled structures
welding
adhesive joints
fatigue
impact
FEM modeling
incremental sheet
forming
joining
brazing
riveting

Published Papers (14 papers)

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Editorial

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5 pages, 223 KiB

Open AccessEditorial

Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles

by Dariusz Fydrych, Andrzej Kubit, Ján Slota and Agnieszka Kowalczyk

Materials 2023, 16(13), 4594; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16134594 - 26 Jun 2023

Cited by 1 | Viewed by 873

Abstract

The pursuit of COx reduction has progressed the construction of transport systems produced using various types of materials to ensure weight reduction while maintaining sufficient functional and quality features [...] Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

Research

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16 pages, 48635 KiB

Open AccessEditor’s ChoiceArticle

On the Springback and Load in Three-Point Air Bending of the AW-2024 Aluminium Alloy Sheet with AW-1050A Aluminium Cladding

by Stanisław Kut, Grzegorz Pasowicz and Feliks Stachowicz

Materials 2023, 16(8), 2945; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16082945 - 07 Apr 2023

Cited by 4 | Viewed by 1399

Abstract

This article presents the results of an analysis of the bending load characteristics and the springback phenomenon occurring during three-point bending of 1.0 and 2.0 mm thick AW-2024 aluminium alloy sheets with rolled AW-1050A cladding. A new proprietary equation was proposed for determining the bending angle as a function of deflection, which takes into account the influence of the tool radius and the sheet thickness. The experimentally determined springback and bending load characteristics were compared with the results of numerical modelling using different models: Model I, a 2D model for a plane deformation state, disregarding the material properties of the clad layers; Model II, a 2D model for a plane deformation state, taking into account the material properties of the cladding layers; Model III, a 3D shell model with the Huber–von Mises isotropic plasticity condition; Model IV, a 3D shell model with the Hill anisotropic plasticity condition; and Model V, a 3D shell model with the Barlat anisotropic plasticity condition. The effectiveness of these five tested FEM models in predicting the bending load and springback characteristics was demonstrated. Model II was the most effective in predicting bending load, while Model III was the most effective in predicting the amount of springback after bending. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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12 pages, 11464 KiB

Open AccessArticle

Determination of Grain Growth Kinetics of S960MC Steel

by Miloš Mičian, Martin Frátrik, Jaromír Moravec and Martin Švec

Materials 2022, 15(23), 8539; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15238539 - 30 Nov 2022

Cited by 3 | Viewed by 1170

Abstract

Fine-grained high-strength low-alloyed (HSLA) steels are used for their advantageous combination of mechanical properties such as high yield strength, tensile strength, ductility, and good formability. These properties are mainly based on applied grain boundary strengthening, which as the only strengthening mechanism allows for the yield strength to increase without a decrease in ductility. Therefore, any changes in grain size lead to irreversible changes in material properties. Such changes also occur during welding in the heat-affected zone (HAZ), where there is a significant change in austenitic grain. In coarse-grain HAZ, this leads to a decrease in yield strength, ductility, toughness, and fatigue strength. The paper experimentally determines the growth kinetics of austenitic grain for fine-grained HSLA steel S960MC. As a result, the values of the activation energy required for grain growth Q and the proportional constant K₀ are determined. Knowing these values is important for numerical predictions of austenitic grain size in the HAZ. Based on these predictions, the changes in yield strength, ductility, toughness, and fatigue strength can be estimated. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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28 pages, 8992 KiB

Open AccessArticle

Multi-Criteria Optimisation of Friction Stir Welding Parameters for EN AW-2024-T3 Aluminium Alloy Joints

by Andrzej Kubit, Tomasz Trzepieciński, Rafał Kluz, Krzysztof Ochałek and Ján Slota

Materials 2022, 15(15), 5428; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15155428 - 07 Aug 2022

Cited by 12 | Viewed by 1767

Abstract

The aim of this research was the selection of friction stir welding (FSW) parameters for joining stiffening elements (Z-stringers) to a thin-walled structure (skin) made of 1 mm-thick EN AW-2024 T3 aluminium alloy sheets. Overlapping sheets were friction stir welded with variable values of welding speed, pin length (plunge depth), and tool rotational speed. The experimental research was carried out based on a three-factor three-level full factorial Design of Experiments plan (DoE). The load capacity of the welded joints was determined in uniaxial tensile/pure shear tests. Based on the results of the load capacity of the joint and the dispersion of this parameter, multi-criteria optimisation was carried out to indicate the appropriate parameters of the linear FSW process. The optimal parameters of the FSW process were determined based on a regression equation assessed by the Fisher–Senecor test. The vast majority of articles reviewed concern the optimisation of welding parameters for only one selected output parameter (most often joint strength). The aim of multi-criteria optimisation was to determine the most favourable combination of parameters in terms of both the smallest dispersion and highest load capacity of the joints. It was found that an increase in welding speed at a given value of pin length caused a decrease in the load capacity of the joint, as well as a significant increase in the dispersion of the results. The use of the parameters obtained as a result of multi-criteria optimisation will allow a minimum load capacity of the joints of 5.38 kN to be obtained with much greater stability of the results. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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19 pages, 12565 KiB

Open AccessEditor’s ChoiceArticle

Determination of CCT Diagram by Dilatometry Analysis of High-Strength Low-Alloy S960MC Steel

by Jaromír Moravec, Miloš Mičian, Miloslav Málek and Martin Švec

Materials 2022, 15(13), 4637; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15134637 - 01 Jul 2022

Cited by 8 | Viewed by 2813

Abstract

High-strength steels are used more than general structural steel due to their combination of properties such as high strength, good toughness and weldability. They are mainly used in the manufacture of heavy vehicles for the mining industry, cranes, transportation, etc. However, welding these grades of steel brings new challenges. Also, a simulation for welding high-strength steel is required more often. To insert a material database into the simulation program, it is necessary to conduct investigations using CCT (Continuous Cooling Transformation) diagrams, welded joints research, and more. To investigate the behavior of S960MC steel during heating and cooling, we used dilatometry analysis supported by EBSD (Electron Backscatter Diffraction) analysis. A CCT diagram was constructed. The transformation temperatures of A_c1 and A_c3 increase with increasing heating rate. The A_c1 temperature increased by 54 °C and the A_c3 temperatures by 24 °C as the heating rate increased from 0.1 °C/s to 250 °C/s. The austenite decomposition temperatures have a decreasing trend in the cooling phase with increasing cooling rate. As the cooling rate changes from 0.03 °C/s to 100 °C/s, the initial transformation temperature drops from 813 °C to 465 °C. An increase in the cooling rate means a higher proportion of bainite and martensite. At the same time, the hardness increases from 119 HV10 to 362 HV10. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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20 pages, 11374 KiB

Open AccessArticle

Three-Dimensional Smooth Particle Hydrodynamics Modeling and Experimental Analysis of the Ballistic Performance of Steel-Based FML Targets

by Andrzej Kubit, Tomasz Trzepieciński, Radosław Kiciński and Kamil Jurczak

Materials 2022, 15(10), 3711; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15103711 - 22 May 2022

Cited by 6 | Viewed by 2099

Abstract

In this paper, shields made of 1.3964 stainless steel bonded to a fiber laminate were subjected to ballistic impact response of 7.62 × 51 mm ŁPS (light projectile with a lead core) projectiles. Additionally, between the steel sheet metal and the laminate, a liquid-filled bag was placed, which was a mixture of ethylene glycol (C₂H₆O₂) with 5 wt.% SiO₂ nanopowder. Numerical modeling of the projectile penetrating the samples was carried out using the finite element method in the Abaqus program. The elasto-plastic behavior of the projectile material and the component layers of the shields was taken into account. Projectile penetration through glycol-filled bag has been performed using the smooth particle hydrodynamics technique. The morphology of the penetration channel was also analyzed using a scanning electron microscope. For the shield variant with a glycol-filled bag between the steel and laminate plates, the inlet speed of projectile was 834 m/s on average, and 366 m/s behind the sample. For the variant where there was no glycol-filled bag between the steel and laminate plates, the inlet and outlet average velocities were 836 m/s, after 481 m/s, respectively. Referring to the steel-glycol-laminate and steel-laminate variants, it can be concluded that the laminate-glycol-laminate is more effective. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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16 pages, 3995 KiB

Open AccessArticle

Effect of Pin Shape on Thermal History of Aluminum-Steel Friction Stir Welded Joint: Computational Fluid Dynamic Modeling and Validation

by Dmitry Olegovich Bokov, Mohammed Abed Jawad, Wanich Suksatan, Mahmoud E. Abdullah, Aleksandra Świerczyńska, Dariusz Fydrych and Hamed Aghajani Derazkola

Materials 2021, 14(24), 7883; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14247883 - 20 Dec 2021

Cited by 39 | Viewed by 2426

Abstract

This article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work on the joint line increased with the pin angle and larger stir zone forms. The simulation results show that in the angled pin tool, more than 26% of the total heat is produced by the pin. Meanwhile, in other cases, the total heat produced by the pin was near 15% of the total generated heat. The thermo-mechanical cycle in the steel zone increased, and consequently, mechanical interlock between base metals increased. The simulation output demonstrated that the frictional heat generation with a tool without a pin angle is higher than an angled pin. The calculation result also shows that the maximum heat was generated on the steel side. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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14 pages, 4926 KiB

Open AccessArticle

Study on Dry Sliding Wear and Friction Behaviour of Al7068/Si₃N₄/BN Hybrid Composites

by Kumar Subramanian, Sakthivel Murugesan, Dhanesh G. Mohan and Jacek Tomków

Materials 2021, 14(21), 6560; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14216560 - 01 Nov 2021

Cited by 15 | Viewed by 3482

Abstract

Hybrid aluminium metal matrix composites have the potential to replace single reinforced aluminium metal matrix composites due to improved properties. Moreover, tribological performance is critical for these composites, as they have extensive application areas, such as the automotive, aerospace, marine and defence industries. The present work aims to establish the tribological characteristics of Al7068/Si₃N₄/BN hybrid metal matrix composites prepared by stir casting route and studied using a pin-on-disc apparatus under dry sliding conditions. The hybrid composite samples were prepared at various weight percentages (0, 5, 10) of Si₃N₄ and BN particles. To investigate the tribological performance of the prepared composites, the wear experiments were conducted by varying the load (20, 40 and 60 N), sliding velocity (1.5, 2.5 and 3.5 m/s) and sliding distance (500, 1000 and 1500 m). Wear experimental runs were carried out based on the plan of experiments proposed by Taguchi. The minimum wear rate was found with the composite material reinforced with 10 wt. % of Si₃N₄ and 5 wt. % of BN. Analysis of Variance (ANOVA) was employed to analyse the effect of process parameters on wear rate and coefficient of friction (COF). The ANOVA test revealed that the weight fraction of Si₃N₄ has more of a contribution percentage (36.60%) on wear rate, and load has more of a contribution percentage (29.73%) on COF. The worn-out surface of the wear test specimens was studied using its corresponding SEM micrograph and correlated with the dry sliding wear experiment results. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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15 pages, 4148 KiB

Open AccessArticle

The Effect of Type-I Photoinitiators on the Kinetics of the UV-Induced Cotelomerization Process of Acrylate Monomers and Properties of Obtained Pressure-Sensitive Adhesives

by Agnieszka Kowalczyk, Mateusz Weisbrodt, Beata Schmidt and Agata Kraśkiewicz

Materials 2021, 14(16), 4563; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14164563 - 13 Aug 2021

Cited by 9 | Viewed by 2049

Abstract

A new method of solvent-free acrylic pressure-sensitive adhesives (PSAs) based on UV-induced cotelomerization products was presented. The key acrylic monomers (i.e., n-butyl acrylate and acrylic acid) with copolymerizable photoinitiator 4-acrylooxybenzophenone in the presence of a selected chain transfer agent (tetrabromomethane, TBM) were used in the UV-cotelomerization process. Moreover, two kinds of UV-photoinitiators (α-hydroxyalkylphenones, HPs and acylphosphine oxides, APOs) were tested. Photo-DSC, viscosity, thermogravimetric, and GPC measurements for cotelomers were performed. The kinetics study revealed that the systems with APOs, especially Omnirad 819 and Omnirad TPO, were characterized by a much higher reaction rate and greater initiation efficiency than HPs systems were. Additionally, the APO-based syrups exhibited a higher solid content (ca. 60–96 wt%), a higher dynamic viscosity (5–185 Pa·s), but slightly lower molecular weights (M_n and M_w) compared to HP syrups. However, better self-adhesive features (i.e., adhesion and tack) were observed for PSAs based on cotelomers syrups obtained using APOs with lower solid contents (55–80 wt%). It was found that as the solids content (i.e., monomers conversion) increased the adhesion, the tack and glass transition temperature decreased and the type and amount of photoinitiator had no effect on polydispersity. Most of the obtained PSAs were characterized by excellent cohesion, both at 20 °C and 70 °C. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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15 pages, 5934 KiB

Open AccessArticle

The Influence of Tool Shape and Process Parameters on the Mechanical Properties of AW-3004 Aluminium Alloy Friction Stir Welded Joints

by Anna Janeczek, Jacek Tomków and Dariusz Fydrych

Materials 2021, 14(12), 3244; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14123244 - 11 Jun 2021

Cited by 50 | Viewed by 3180

Abstract

The purpose of the following study was to compare the effect of the shape of a tool on the joint and to obtain the values of Friction Stir Welding (FSW) parameters that provide the best possible joint quality. The material used was an aluminium alloy, EN AW-3004 (AlMn1Mg1). To the authors’ best knowledge, no investigations of this alloy during FSW have been presented earlier. Five butt joints were made with a self-developed, cylindrical, and tapered threaded tool with a rotational speed of 475 rpm. In order to compare the welding parameters, two more joints with a rotational speed of 475 rpm and seven joints with a welding speed of 300 mm/min with the use of a cylindrical threaded pin were performed. This involved a visual inspection as well as a tensile strength test of the welded joints. It was observed that the value of the material outflow for the joints made with the cylindrical threaded pin was higher than it was for the joints made with the tapered threaded pin. However, welding defects in the form of voids appeared in the joints made with the tapered threaded tool. The use of the cylindrical tool resulted in higher values for about 37% of mechanical properties compared with the highest result for the tapered threaded joint. As far as the parameters were concerned, it was concluded that most of the specimens were properly joined for a rotational speed of 475 rpm. In the joints made with a welding speed of 300 mm/min, the material was not stirred properly. The best joint quality was given for a rotational speed of 475 rpm as well as a variety of welding speed values between 150 and 475 mm/min. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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20 pages, 13068 KiB

Open AccessArticle

Conceptual Study and Manufacturing of a Configurable and Weld-Free Lattice Base for Automatic Food Machines

by Alessandro Pirondi, Andrea Liberini and Flavio Rocchi

Materials 2021, 14(7), 1692; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14071692 - 30 Mar 2021

Cited by 1 | Viewed by 1801

Abstract

The study is aimed at developing a modular lattice base for automatic food machines, starting with a solution already patented by some of the authors. In this case, welded carpentry modules were interlocked with a system of profiles and metal inserts, also in welded carpentry, and the union was stabilized by structural adhesive bonding. Since welding involves long processing times and thermal distortions to be restored later, the driver of this study is to limit the use of welding as much as possible while increasing the modularity of the construction. For this purpose, various solution concepts have been generated where a common feature is the presence of rods of the same geometry and section to be joined together in configurable structural nodes. The concepts are qualitatively evaluated in light of the requirements, and the selected concept is digitally and physically prototyped. The prototype has been in service from over 5 years without showing any problems whatsoever. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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10 pages, 3050 KiB

Open AccessArticle

Influence of the Thermal Cutting Process on Cracking of Pearlitic Steels

by Lechosław Tuz, Aneta Ziewiec and Krzysztof Pańcikiewicz

Materials 2021, 14(5), 1284; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14051284 - 08 Mar 2021

Cited by 3 | Viewed by 1802

Abstract

The paper presents research results of the influence of heat input into high carbon rail steel during cutting processes on microstructure transformation and cracking. The massive block of steel prepared for rail rolling processes was cut and examined by nondestructive magnetic testing and destructive testing by microscopic examination and hardness measurements. The results show unfavorable microstructure changes where pearlite and transformed ledeburite were obtained. The effects of the presence of such microstructures are high hardness near to cutting surfaces (above 800 HV) and microcracks which grow into low hardness block cores during rolling and rail shaping. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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19 pages, 7665 KiB

Open AccessArticle

Ultimate Load-Carrying Ability of Rib-Stiffened 2024-T3 and 7075-T6 Aluminium Alloy Panels under Axial Compression

by Ján Slota, Andrzej Kubit, Tomasz Trzepieciński, Bogdan Krasowski and Ján Varga

Materials 2021, 14(5), 1176; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14051176 - 02 Mar 2021

Cited by 10 | Viewed by 3289

Abstract

Stringer-stiffened panels made of aluminium alloys are often used as structural elements in the aircraft industry. The load-carrying capacity of this type of structure cannot relieve the reduction in strength in the event of local buckling. In this paper, a method of fabrication of rib-stiffened panels made of EN AW-2024-T3 Alclad and EN AW-7075-T6 Alclad has been proposed using single point incremental forming. Panels made of sheets of different thickness and with different values of forming parameters were tested under the axial compression test. A digital image correlation (DIC)-based system was used to find the distribution of strain in the panels. The results of the axial compression tests revealed that the panels had two distinct buckling modes: (i) The panels buckled halfway up the panel height towards the rib, without any appreciable loss of rib stability, and (ii) the rib first lost stability at half its height with associated breakage, and then the panel was deflected in the opposite direction to the position of the rib. Different buckling modes can be associated with the character of transverse and longitudinal springback of panels resulting from local interaction of the rotating tool on the surface of the formed ribs. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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13 pages, 2497 KiB

Open AccessArticle

Influence of Acrylic Acid on Kinetics of UV-Induced Cotelomerization Process and Properties of Obtained Pressure-Sensitive Adhesives

by Agnieszka Kowalczyk, Mateusz Weisbrodt, Beata Schmidt and Konrad Gziut

Materials 2020, 13(24), 5661; https://0-doi-org.brum.beds.ac.uk/10.3390/ma13245661 - 11 Dec 2020

Cited by 11 | Viewed by 2343

Abstract

A new environmentally friendly method of photoreactive pressure-sensitive adhesives (PSAs) preparation was demonstrated. PSAs based on n-butyl acrylate (BA), acrylic acid (AA) and 4-acryloyloxy benxophenone (ABP) were prepared via the UV-induced cotelomerization process in the presence of a radical photoinitiator (acylphosphine oxide) and telogen (tetrabromomethane). Hydroxyterminated polybutadiene was used as a crosslinking agent. Influence of AA concentration (0–10 wt %) on kinetics of the cotelomerization process was investigated using a photodifferential scanning calorimetry method, selected physicochemical features of obtained photoreactive BA/AA/ABP cotelomers (molecular masses, polydispersity, monomers conversion and dynamic viscosity) and self-adhesive properties of obtained PSAs (adhesion, tack and cohesion) were studied, as well. It turned out that AA content is the important factor that influences monomers conversion (thereby the volatile parts content in prepolymer) and PSAs’ properties. As the acrylic acid content increases, the reaction rate increases, but the total monomers conversion and the solid content of the prepolymer decreases. Additionally, the adhesion and cohesion of PSAs were grown up, and their tackiness decreased. However, the AA content has no effect on molecular weights (Mw and Mn) and polydispersity (c.a. 1.5) of photoreactive cotelomers. The optimal AA content necessary to obtain a prepolymer with low volatile parts content and good PSA properties was determined. Full article

(This article belongs to the Special Issue Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles)

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