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The purpose of this paper is to present a latest update on halogen‐free base materials that are lead‐free compatible and have enhanced electrical properties.

Numerous halogen‐free flame retardants are screened in laboratory conditions for a wide arrange of properties. Once suitable candidates are found, they are compounded and processed into copper‐clad laminates and a wide variety of properties are tested.

Several formulations are found that are lead‐free compatible and that has enhanced electrical properties. Surprisingly, some thermal properties are found to be superior to traditionally halogenated laminates.

The research here only presents the halogen‐free properties of a bare, unpopulated printed wiring board with no build up of inner layers and devoid of solder mask. Further work needs to be done on full circuit assemblies to properly evaluate the impact of removing halogens from interconnecting packages.

The paper details the material property differences between various halogen‐free materials as compared to halogenated materials. A method to model composite properties is also discussed.

This study explored Croatian nursing students' knowledge and attitudes regarding brominated flame retardants (BFRs) as indicators of their predisposition to educate future patients. The purpose of the study was to identify knowledge gaps and barriers and to propose possible remedies.

The cross-sectional survey was conducted on a convenience sample of 114 nursing students at undergraduate and graduate levels from three Croatian universities during the winter semester in the academic year 2018–2019. Descriptive and inferential statistical  analyses were performed using STATISTICA 13 software.

Slightly over half of the students (58.49%) were knowledgeable of BFR health effects and 45.28% showed knowledge about its presence in the environment. Only 33.02% of students identified prenatal exposure effects and 24.53% answered correctly about legislative actions. Participants expressed modest interest in the topic (M = 3.15, SD = 1.35). Although informing the public on the health consequences of BFRs was important to them (M = 4.18, SD = 1.03), they did not perceive health-care providers as primarily responsible for communicating that information.

There is a need to enhance related content in the curriculum to improve students' knowledge. Raising students' awareness regarding the role of nurses in clinical and policy arenas is proposed to facilitate active participation in improving environmental health.

To give an overview of the mechanisms by which brominated flame retardants (BFRs) used in the electronics industry enter, and are transported, in the environment. The potential impacts of BFRs on living organisms are also outlined.

The paper provides an explanation of the environmental issues and impacts on living organisms of BFRs that are used extensively in electrical and electronic applications. It is compiled using information from examples of the published literature and seeks to give an explanation for the increasing pressure on the electronics industry to limit the use of BFRs and to introduce non‐halogenated alternatives.

Despite typically being incorporated into thermoplastic and thermosetting polymers, BFRs have been found to enter the environment and to accumulate in regions of the world. The mechanisms by which this migration can occur are complex and influenced by a wide variety of factors. However, such migration has lead to BFRs being found in areas such as the artic, which are far from their original source. They are also able to accumulate up the food chain where they can become concentrated enough to cause health problems for mammals and humans.

This short review paper can only provide an introduction to how BFRs enter the environment. Nevertheless, there is a growing amount of evidence that BFRs can have a negative impact in the environment and it seems likely that this will lead to calls for the further restriction of these undoubtedly valuable materials.

The paper gives an introduction to the fate of BFRs and discusses how they are able to migrate from the products they are used to protect and into the environment. Their accumulation in the food web and impact on living organisms are also discussed.

With the ever increasing demands for high performance electronic devices there is a need for circuit board laminates that have enhanced properties when compared to conventional materials such as the widely used epoxide‐based FR4 laminates. Equipment manufacturers require boards with better mechanical stability and improved electrical characteristics. At the same time, new environmental legislation is set to drive electronics assembly temperatures much higher as manufacturers start to use lead‐free soldering processes. The legislation is also raising questions about the long‐term viability of brominated resins as the basis for imparting flame retardancy to laminates. Fortunately, laminate manufacturers have responded to these challenges by developing and introducing a wide range of new laminates that address these issues. This paper describes some of these challenges and gives an introduction to the new high performance laminates that are finding increasing use. It also highlights the need for chemical processes used in the manufacture of interconnects with laminates to be specifically optimised for the chosen substrate material.

To present an overview of the current status of the RoHS directive and its implications for the printed circuit board (PCB) industry.

A review paper detailing the requirements of the RoHS directive, the materials that are proscribed, where they are found and the impacts on PCB fabrication and assembly.

The main implications of RoHS for the PCB industry are related to the proscription of lead and the move to lead‐free assembly. Tin‐lead HASL finished boards will no longer be allowed and new laminates may be needed to accommodate the higher soldering temperatures associated with lead‐free assembly. There is growing pressure to move away from the use of brominated flame retardants, even though the standard materials used in FR4 type laminates are not proscribed.

Manufacturers need to be aware of the implications of the RoHS directive, not just in terms of compliance but also from a materials selection and reliability perspective.

The paper details how the RoHS directive impacts PCB manufacturing and assembly and highlights the changes needed to enable reliable lead‐free assembly within the context of legislative compliance. Actions necessary to ensure compliance are also detailed.

This paper seeks to give an overview of problems arising with the change to lead‐free soldering and to give guidance on possible counter actions in the context of the chemical structure of the base material.

The paper contains a number of correlations between different physical measurements and their impacts on real life processing conditions. The problem areas are highlighted and the corrective actions that need to be taken on the base materials are described. The impact of the choice of flame retardant on material properties is demonstrated.

Results suggest that conventional resin systems seem to be still suitable for standard FR‐4 applications with only a few reflow cycles. Higher thermally resistant products are necessary for more complex structures that require multiple reflow cycles. There are basically two ways to increase the thermal resistance. Replace dicyandiamide by a phenolic hardener or change to a bromine‐free flame retardant. Both approaches are successful in raising the decomposition temperature, with the latter having the additional advantage of achieving better electrical performance and lower density.

The value of the paper lies in its ability to provide guidance on the critical base material properties. It describes the change in physical properties that laminates will see when moving up in temperature to facilitate lead‐free soldering. Selection criteria for base materials are given in order to neutralize the impact of the higher temperature.

There was a time when these compositions could command only a limited interest, but the range of applications is now so wide, that demand has expanded as an ever increasing clientele is using them.