Product Focus: Blowing Agents

Today foamed plastics and rubbers are present, in a clear or more hidden way, in many objects familiar to us: popular mats in sport centers or used for excursions; car seats or bags covered with synthetic leather; high quality floorings; or car dashboards.
Initially the applications of blowing agents  were related to three main benefits:

Insulation: the cell structure generated by gas released contributes to diminish the transmission of noise, the absorbtion of vibrations, and the creation of barriers to retain the heat or avoid the humidity.

Soft touch: foamed and elastic surfaces, in direct or indirect physical contact,  contribute to confort of users. Resilience of foams create a cushioning effect.

Durability:  foamed plastic materials can replace natural materials, improving mechanical, resistance and recyclability properties.
But the evolution of the world during the last decades, with an increasing and real concern about emissions of CO2, is assigning the blowing agents an important new mission, which is the creation of plastic lightweight materials. The benefit obtained is double: on one hand making transport less expensive, and on the other hand reducing the consumption of plastic raw materials.
Two key industrial sectors are demanding more and more foamed materials: the construction and the automotive. Both are directly responsable of most of the emissions of CO2. In the case of construction, the house 0 emissions is indeed a real target, sustained in the consumption of renewable energy sources but especially in the perfect isolation, for which foamed materials are relevant. In the automotive, until the electric car is a real alternative, the strategy of manufacturers is to reduce as much as possible the consumption of oil by lowering the weight of the car.
Summarizing, we can say today that blowing agents are green materials, which combate the climate change, reducing the impact of the human being and improving the living standards of the people.
The evolution of blowing agents cannot be fully understood without the existence of the azodicarbonamide.

That exothermic foaming agent is the most widespread, for several reasons:
It is extremely versatile. On one hand ADCA can be used with most used plastics (polyethilene, polypropilene, PVC, EVA, PS), rubber and thermoplastic elastomers. This is possible because the temperature of decomposition of azodicarbonamide can be quite precisely adjusted by using activators. On the other hand ADCA works well in common industrial processes such as extrusion, calendering, coating, press-molding and even injection molding. Finally ADCA can be combined with other blowing agents in order to control the foaming process, changing the properties of the end foam.

During decomposition ADCA creates an internal close cells matrix, valuable for insulation and soft touch properties. That structure can be modified by using grades with different particle size, or with crosslinkers which retain the gas.

It is very efficient. ADCA is the highest gas releasing foaming agent. What combined with its affordable price makes it the most competitive one.

Regulatory aspects are getting more and more importance in today organizations. The ADCA is worked since many years in a safe way by the users, reducing the exposure to very low values. Working processes assure that the ADCA is almost 100% fully decomposed in the final foamed product, as well as any other potential byproduct generated during that process.
New requirements in the industry are pushing more and more the azodicarbonamide to be consumed in masterbatch form.
First of all, industrial processes looking for more productivity, with faster production and less energy consumption, are in favor of pre-dispersed azodicarbonamide. The usage of powder requires more time and energy.
Second reason is the quality in the end product: masterbatch of blowing agents is easier to be dosed, assuring a much more regular foaming, what gives better structural properties, no matter the thickness of the foam. In this respect, there are two factors directly influencing the good dispersion of the masterbatch within the plastic: first of all the choice of the carrier used, that has to be compatible both with the plastic and the foaming agent; and afterwards the size of the pellet.
Third, the use of masterbatch of azodicarbonamide is recommended to ease the handling of that substance: no ATEX related issues, no need of special protection measurements and much easier logistics.
Finally, in case that the ADCA is used in a non safe way, the consumption of masterbatch allows to solve the matter with no investment by the end user.
In order to fulfil necessary cost requirements, the answer from the ADCA masterbatch industry has been the increase of the loading of foaming agent within the pellet or granule.
In-between the use of masterbatch and the pure powder of ADCA, there are other possibilities which allow the achievement, total or partially, of some of the benefits given by masterbatch. We refer to the use of powder with modified properties. For instance, ADCA low-dust, free-flowing or dumpe; but also the pre-addition of activators to pure ADCA, creating high performance products.    
Hebron, as specialist in foaming agents and manufacturer of masterbatch, and world leader in azodicarbonamide, is able to provide industrial customers the appropiate technical support to develop a new project. It is our job to select the the needed blowing agents (exothermic or endothermic), other additives and correct carriers to produce the suitable masterbatch. 
We are to provide standard products or Taylor made ones, in that case working with needed confidentiality with industrial customers. Our facilities (laboratory and pilot plant) allow us to make quick developments.