Bioplastics ‘revolution’ underway but new materials need different processing

CosmeticsDesign.com USA spoke to Hiram Santana from Cosmetic Specialties International (CSI) - which has handled a number of bioplastic resins in partnership with cosmetics brands including Mirel’s PHA resin (polyhydroxyalkanoate) as well as PLA (polylactic acid)-based materials - about how to get the most out of the bioresins currently available on the market.

According to the business development manager for the company, bioplastics have all the potential of their petroleum-based cousins but they require different processing.

While Santana refers to the introduction and development of the materials as a revolution in the plastics industry, he said it is dangerous to assume they can be processed in exactly the same way as their traditional counterparts.

“We will be able to do everything with bioplastics that we can do now with oil-based materials, but in a different way,”​ he told CosmeticsDesign.com USA.

Three main processing challenges​

Most of the processing challenges surrounding the materials fall into three main areas, he said, the heat resistance of the resins, their barrier properties and how they respond to impact.

Most bioplastics available today are more sensitive to heat than petroleum-based materials, Santana explained, meaning that significantly less energy and production time is needed to mold them. For cosmetic marketers, the benefits mean a lower-carbon footprint for earth-friendly components that can be delivered faster and leave less of an impact on the environment.

“Mirel has made incredible advances in this area in recent years, realizing that they needed to adapt the material to processing and plastic-injection molding equipment already in use,”​ he said.

However, for Santana, different bioplastics and recycled resins do behave differently and manufacturing know-how is paramount to success.

“Not all companies are able to deal with these materials and too often marketers expect them to run the same way. We have been working through the learning curve for several years now to deliver bioplastics processing solutions.” ​

The barrier properties of the material can also pose challenges for marketers and manufacturers alike and here Santana explained that testing is critical.

“Regardless of what new material you use, bioplastics or otherwise, compatibility, moisture resistance and other tests may be required depending on the material; you can’t just assume that the packaging will be suitable for all formulations. This is especially true when developing packaging for formulations that include sunscreen, oils and other ingredients.”​
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Another challenge can also be material strength or resistance to impact. Some bioplastics are less rigid than petroleum-based materials which can affect how they are handled once molded.

One technical stumbling block that also affects the appearance of the product and therefore consumer acceptance is the potential for coloring the bioplastics resins. Here the industry has made progress, Santana explained, although there are still improvements that need to be made. Today a wider range of colors that bond with bioplastic resins are available.

“Mirel is currently developing additional color concentrates to bond with bioplastic resins that meet compostability and biodegradability standards. CSI is working closely with Mirel on this.”​

Biobased not necessarily biodegradable​

Although an important advance, the sustainable nature of the feedstock does not necessarily mean that the material can be disposed of in a more environmentally friendly way – a distinction which Santana believes is not yet clear in the minds of most consumers.

In addition, even if a material is biodegradable it will not degrade if put into the landfill so information about how to best dispose of it, is necessary.

Education is needed to clarify in the minds of consumers, and clients, the environmental profiles of these new ingredients. Although CSI does not have direct contact with consumers, Santana said companies such as this do need to help get the right information out there.

“Our company has a role to play in the education but we cannot do it alone, this has to be a combined effort from resin makers, converters and the companies that will be selling these products to the consumers,” ​he said.

“The first thing we have to do is to find out why a company is investigating biobased materials. Is it in response to consumer demand, a quick fix to try to improve the reputation of the product, and is it the biobased aspect that is of interest or biodegradability? We then advise accordingly.”​

In addition, Santana noted that regulatory bodies are becoming increasingly strict on greenwashing claims so companies will need to make full use of the technical data provided by the resin makers to back up their claims.