Additives are crucial to plastics formulations. Specialty additives are one of the most dynamic segments of the plastics industry. A specialty additive insight that occurs suddenly and unexpectedly is a flash of inspiration. Knowledge or insight gained by looking into the future of polymer formulation is helpful. A sudden burst of insight about the future will produce a new and radically different way of using advanced plastic additive solutions that will open up hidden product development opportunities. Let’s tour eight key polymer additive segments and explore sixteen trends of the future!
Additives for Packaging
Fragrance and Flavor Packaging Enhancement
ScentSational Technologies, which develops/licenses olfaction packaging technologies, has introduced CompelAroma which uses ‘Encapsulated Aroma Release’ technology to add particularly engineered food grade flavors to a plastic packaging structure to enhance a product‘s aroma profile. For example, CompelAroma contained in package walls or liners can appreciably extend the period of time that a package such as coffee remains on the shelf by maintaining a desirable aroma. ScentSational has also created technology to incorporate fragrance and flavor in single serve beverage container closures/closure liners designed to be consumed directly from the bottle. The technology allows the beverage bottle headspace to be filled with aromas that provide a greater consumer experience. ScentSational technology is also being used to add fragrance to the closures of shampoo, laundry detergents, and other cleaning, health and beauty products to allow consumers to sample a product's scent, without disturbing the product seal.
Packaging Film Advanced Slip and Antiblock Additives
Slip and antiblock additives are widely used to modify the surface of polymer film and sheet to facilitate performance in fabrication, packaging, and/or end-use applications. Without their use most film would be hard to process, as the material would otherwise not slide readily over itself or other surfaces in converting, packaging, and printing equipment. Film layers have a tendency to adhere when pressed together during processing or on being stacked after cutting. A range of slip and antiblock additives are available including primary, secondary, non-migratory, and other slips, in addition to organic and inorganic antiblocks, and diverse slip–antiblock combinations. In many applications such as single and multilayer bags, wrap and other packaging these additives must have the appropriate food contact approvals. While often added directly by the resin producer, slip and antiblocks are most commonly added by the processor via a range of masterbatches to adapt additive levels to the application.
Biopolymers provide new market prospects for packaging additives such as slips and antiblocking materials. Many of the emerging biopolymers are particularly tacky and tend to stick to themselves and to metal take-up rolls and other surfaces involved in processing. A critical factor for PLA (polylactic acid) additives is compatibility with the resin to maintain clarity. Furthermore some companies like Metabolix and Meredian say they will only use biobased additives with their resins. Clariant Masterbatches has developed new CESA-slip and CESA-block masterbatches for biopolymers like PLA employed by the packaging and film industry. Its CESA-naturslip additives, based on pure naturally occurring waxes such as beeswax, have minimal impact on transparency and give very good slip properties with a coefficient of friction (CoF) close to that achieved by modern synthetic waxes.
Sukano slip/antiblock masterbatches for PLA film and sheet (dc S511) include optical brighteners. They have food contact certification and are also approved as suitable for composting. Additionally PolyOne’s OnCap Bio additive masterbatches include slip and antiblock masterbatches designed for specific use with biodegradable resins such as PLA. Ampacet Corporation is another masterbatch provider that has developed slip and antiblock concentrates for PLA and PHA.
Renewably Sourced PET
The world’s first global bio-PET integrated supply chain is being established by Toyota Tsusho. The supply chain includes procurement of bio-ethanol, production of bio-mono ethylene glycol (bio-MEG), PET tolling, and bio-PET marketing. Braskem will supply the bio-ethanol from Brazil. Greencol Taiwan Corp (GTC), a 50/50 JV between Toyota Tsusho and China Man-Made Fiber Corporation, will produce bio-MEG using the sugar-based ethanol as feedstock. Greencol will produce the bio-MEG in a new facility in Kaohsiung, Taiwan. The bio-MEG will be handled/ supplied by Toyota Tsusho to PET toll manufacturers in Asia. The off-take of bio-PET from toll manufacturers will be marketed by Toyota Tsusho to end-users in Japan, Europe and the US. The companies expect to toll-produce and sell 200,000 tons/year of bio-PET.
Global Bio-PET Supply Chain; [Source: Toyota Tsusho]
Non-Food Sourced High Performance Bioplastic
A durable new high performance bioplastic developed by NEC is suitable for plastic components for electronic equipment. This first-of-its kind durable new bioplastic is produced from stable non-edible plant resources. It is based on cellulose from plant stems and cardanol, a primary component of cashew nut shells. The plant stems and nut shells are abundant resources often discarded as byproducts of the agricultural processing industry. Use of these non-edible plant sources as the main components of the new bioplastic will therefore have little or no impact on the production of food crops. Cashew nuts are widely cultivated in India and Vietnam and NEC says it is assured of a stable supply of cardanol. The durable bioplastic boasts a high plant composition ratio of more than 70%. Other cellulose based plastics are typically heavily loaded with petroleum based plasticizers which results in a bioplastic with a low plant component ratio and poor durability including insufficient heat and water resistance or are blended with petroleum based plastics to improve strength and thermal resistance. Cardanol has a unique molecular structure that consists of a rigid phenol component and a flexible, hydrophobic, linear hydrocarbon component. Cellulose is the main ingredient of the bioplastic and is bonded with the oil-like cardanol which has been modified to enhance its reactivity.
Cellulose / Cardanol Based Bioplastic; [Source: NEC]
NEC’s new bioplastic has important advantages compared to PLA and cellulose acetate as follows:
• Its molding time is <50% that of PLA and comparable to conventional cellulose-based and petroleum-based plastics
• More than twice the heat resistance of PLA and 1.3 times that of cellulose acetate
• Twice the strength of existing PLA and comparable strength to conventional cellulose acetate
• Water resistance is comparable to PLA and approximately 3 times better than cellulose acetate
Cellulose / Cardanol Based Bioplastic (Green Bar) Performance Features; [Source: NEC]
NEC expects the new bioplastic to be commercialized by shortly at a price lower than PLA and competitive with petroleum based plastics. NEC believes the durability achieved by the new bioplastic will make it highly suitable for electronics applications.
Open Source Strategy to Spur Injection Molded Bioplastics Development
A page is being taken from the computer industry to spur innovation and drive biopolymers more widely into injection molding applications. NatureWorks is making formulation and compounding procedures for its high-heat resistant, high impact, bioresin Ingeo 3801X openly available. The company has ‘drawn back the curtain’ on development of the grade to share the technology and provide transparency on how the solution was arrived at including what was used to tailor properties/processing characteristics and why. Information is also openly available for high heat formulation Ingeo HHIM 670-82-01. With formulation in hand, independent specialty resin companies and brand owners with captive operations will be in a position to use Ingeo as the foundation for biobased injection molded products and components. NatureWorks also expects the details of the formulation can serve as a basis for R&D in further tailoring biobased solutions for the semi-durable plastics market. The company has also taken a similar ‘pull-back-the-curtain’ approach with its foam grade material, 8051D, but as that grade had just a small group of potential users it was done on a more one-to-one basis. NatureWorks is now also offering for sale a range of polymer-grade lactides. Lactide partners can also take advantage of a new Ingeo licensee package. Under select terms, the company will supply access to trademarks and application patents needed to support and enable the wider adoption of Ingeo biopolymers.
Ingeo Injection Molding Compound Formulation; [Source: NatureWorks]
Heat Resistant Plant Based PLA Molding Compound
Highly heat resistant PLA Molding compound MBA900H co-developed by Panasonic Electric Works and Teijin Ltd. is composed of 80% plant-based renewable feedstock. The compound has significantly reduced molding cycle time around half that of conventional PLA compounds. Conventional PLA has low heat resistance and limited injection-molding capability because of its longer molding cycle time. Other molding compounds have been developed by mixing PLA with petroleum based plastics but attaining the desired levels of heat resistance and moldability has required a high ratio of oil based plastic. In Teijin’s‘Biofront’ bioplastic, a highly heat resistant PLA is used in the compound. Teijin’s Biofront stereo-complex PLA has a melting point of approximately 210ºC, significantly higher than that of conventional PLA. It also shows better hydrolytic stability and achieves semi-crystallization in just 20-25% of the time required with conventional PLA. The stereo-complex PLA made with conventional ‘left handed’ poly-L-lactic acid combined with its ‘right-handed poly-D-lactic acid that has much higher heat resistance. 8Biofront PLA of 50/50 L and D lactides achieves a semicrystalline resin with a melting point 40ºC higher than conventional PLA, and on a par with the heat resistance of petroleum-based PBT. Panasonic Electric Works’ proprietary compound-design and production technologies were also used in the development. The compound will initially be used in the housings of cell phones and other mobile devices and digital consumer electronics. Panasonics’ initial goal is 1000 tons annual production. Teijin operates a Biofront demonstration plant with a capacity of 1000 tons/year and expects to increase its capacity to 5,000 tonnes/year.
Comparison of Molding Cycle Time (Red, Biobased MBA900H); [Source: Panasonic Electric Works, PEW]
Formulations and Transparency
Solasorb Inorganic UV Light Absorber
Solasorb, a novel type of inorganic UV light absorber from Croda Polymer Additives is based on ultra fine metal oxides (TiO2 and ZnO) that provide stable dispersion, low migration, and long-term protection. In comparison to traditional nanoparticle additives, this UV protection material is said to deliver:
• Low migration
• Long-term UV protection
• Greater dispersion
• Minimal effect on transparency
Careful particle size control yields good UV absorbance coupled with significantly improved transparency compared to other metal oxide powders. Its use in plastics for packaging applications reduces color change in cosmetics and personal care products and prevents vitamin loss, development of off-tastes and odors in beverages.
NanoArc ATO Infrared Protection
NanoArc Antimony Tin Oxide (ATO) nanoparticle additives by Nanophase Technologies Corporation can be incorporated into clear film and sheet to absorb IR but not visible light. It provides this benefit by absorbing energy in the near-IR region and reflecting energy at longer IR wavelengths, while maintaining excellent transparency in the visible region. In products like skylights it prevents heating of interior space. The incorporation of NanoArc ATO into surface coatings is an effective means of managing radiant heat without adversely impacting the optical clarity or other desirable physical properties of the article on which it is applied.
To be continued ........
Donald V. Rosato, Ph.D.
Dr. Donald V. “Don” Rosato of PlastiSource Inc. has been actively involved with plastics, moving from aerospace development to leading resin suppliers from the late ‘60s to early ‘90s, before starting his own 20 year old prototype manufacturing, product development, and technical market advisory firm. He was involved with firsts developing the Apollo 11/12/13 composite moonship legs, America’s Cup/Olympic luge/bobsled parts, PET & recycled PVC bottle manufacturing, barrier packaging, super-tough nylons, engineered plastic blends/alloys, high performance LCPs & related ultra-resins, DARPA/ARPA aerospace/defense/alternative energy electronics, biocomposites/green resins, greenbuilding/LEED end uses, electrically/thermally conductive polymers, specialty additive compounds, TPEs/synthetic rubbers, advanced molding technologies, and clean thermoset resins. He continues into his 6th decade to author/present multiple global webinars, papers and books, analytical reports, and online plastic columns.
Don has wide-ranging technical and marketing plastic industry experience from product development, through production, to marketing, having worked for Northrop Grumman, Owens-Illinois/Graham, DuPont/Conoco, Celanese/Ticona, and Borg Warner/G.E. Plastics. He has developed numerous polymer related patents, participates in many trade groups (SPE, SPI, PIA, CPPIA, SAMPE), and is involved in these areas with PlastiSource, Inc. He earned his BS Chemistry, Boston College; MBA, Northeastern University; M.S. Plastics Engineering, University of Massachusetts Lowell; Ph.D. Business Administration, University of California, Berkeley, and has extensive executive management training.