A lot has changed in the plastics additive segments in the last few years. The need for product differentiation is the primary driving force behind the wealth of new additives those are being incorporated in the plastics products. These additives are tailor-made systems to meet ever changing applications of plastics. The plastics additives global market of $46.3 B by year end 2014 has been growing at a CAGR (Compound Annual Growth Rate) of 4.5% over the last five years. Property modifiers have the largest share of the market, worth an estimated $22.8B by year end 2014. New market development is growing rapidly in Asia and likely to do so in coming years.
In his final part of the article, Dr. Rosato reviews some of the latest developments in additives and describes how these additives nanotubes to glass fiber could change future of plastic products.
Flame Retardant Filled Halloysite Nanotubes
To replace halogenated flame retardants, nanotechnology comes into play. NaturalNano Inc., a developer of advanced nanomaterials and additive technologies based on halloysite clay nanotubes, is developing a range of products with extended release properties including flame retardants for furniture applications based on its family of Pleximer products. The nanotubes, with their hollow structure, can be filled with additives to create a slow or extended release of the additive concentrate. For FR applications, the company believes it can develop flame-retardant compounds that would release only under extreme heat conditions. NaturalNano believes that commercializing Pleximer with extended release capabilities is not only the next step in expanding their product offerings, but also is an important next stage in the evolutionary development of nanocomposites.
Flame Retardant Phosphonate Polymers
FRX Polymers has commercialized its proprietary phosphorous-derived inherently flame retardant polymer as an answer to concerns regarding halogen-based flame retardants. The company which holds 35+ patents and patent applications is developing entirely new polymers based on phosphonate. Its polyphosphonates are being commercialized as a homopolymer (FRX100) and polyphosphonate/polycarbonate block copolymers FRXCO25, FRXCO35, and FRXCO85 with 25%, 35%, and 85% polyphosphonate content respectively. With its high phosphorus content (10.8%) polyphosphonate homopolymers offer the highest limiting oxygen index (LOI) of all known thermoplastics. FRX 100 is being marketed as a halogen free flame retardant for use with other resins. In comparison with typical FR additives, it has the advantage of not affecting host resin mechanical properties. In terms of flame retardant performance the material has achieved a UL V0 rating at 0.75mm with full transparency and a glow-wire test rating of 825ºC.
The clear, tough, and inherently very flame-retardant engineering resins have some similarities to polycarbonate. The glass transition for the neat homopolymer is 107ºC and 135 ºC as a 65/35 polycarbonate/polyphosphonate copolymer which is comparable to pure polycarbonate’s 147 ºC. FRX copolymers are moldable or extrudable thermoplastics which depending on copolymer ratio have higher melt flow and flame resistance than polycarbonate but lower heat and impact resistance.
S-1 Glass, Higher Performance at Lower Cost
AGY Holdings Corporation recently introduced its trademarked S-1 Glass high performance rovings for use in long-fiber reinforced thermoplastics. Designed for use with a range of resins including polycarbonate (PC), polyetherimide (PEI), polybutylene terephthalate (PBT) and nylon (PA 6/6), S-1 Glass was created to bridge the cost–performance gap between E-Glass and higher performance S-2 Glass fibers. Intended for industrial applications, such as compressed natural gas (CNG) storage, wind energy, and military armor end uses, these glass fibers achieve desired levels of mechanical properties in reinforced thermoplastics at much lower levels of glass fiber than E-Glass, providing better processing with higher impact performance. Compared to traditional E-glass, the S-1 Glass has higher hydrolytic stability, a 30 to 45% improvement in tensile properties and an 18 to 25% improvement in tensile modulus. It has been demonstrated that an LFT (long fiber thermoplastic) with 32% S-1 Glass fiber content can deliver the same performance as a 60% E-glass filled product. The lower fiber content provides higher impact, better aesthetics and easier processing.
S-1 Glass roving has received approval for use in thermoset epoxy based wind turbine blade applications by Germanischer Lloyd, a classification society based in Germany that is the foremost international certification body in the wind energy sector. The product’s better performance/cost balance allows manufacturers to optimize wind blade design to lower blade weight, or extend blade length without increasing weight.
Weight Reducing Stiffness/Impact Modifier
Milliken Chemical’s Hyperform 803 is an inorganic fibrous mineral designed to deliver an outstanding balance of impact strength and stiffness while reducing weight by up to 15% versus traditional mineral filled systems. The material offers comparable performance at lower weight versus competing mineral additives such as talc.
While weight had customarily been reduced by replacing metal with high performance or engineering plastics, advances in resin, additive and process developments have bridged the gap between polyolefins and engineering resins. Glass reinforcements for polyolefins have enabled them to achieve performance similar to more expensive and heavier engineering resins but are known to cause deterioration of the surface properties of the molded parts. Hyperform 803 can produce a surface finish comparable to that of a talc-filled compound allowing polypropylene to be used in automotive applications beyond concealed structural parts. This excellent surface finish versus glass-filled polypropylene allows polypropylene compounds to be used in highly visible bumper and door panel components.
PVC and Sustainability
Alternative Plasticizers–Non Ortho-Phthalate Esters
Lanxess’ phthalate-free Mesamoll/Mesamoll II are not di-isononyl cyclohexanedicarboxylate (DINCH) products that are produced through catalytic hydrogenation of di-isononyl phthalate. DINCH is the most widely used phthalate plasticizer substitute. In the EU, DINCH is not listed in directive 2005/84/EC which bans the use of certain phthalates in toys and childcare articles and thus can be used safely in these products. The main difference between Mesamoll II and Mesamoll is the former's reduced volatility. With growing demand for phthalate-free plasticizer, Lanxess is expanding its Mesamoll family production capacity by 40%. Sales of the Mesamoll product line is growing at an annual rate of roughly 15%. The additional capacity is available at the Krefeld-Uerdingen facility. Mesamoll II received FDA approval for use in products that come in contact with aqueous-based foodstuffs. Mesamoll II has now taken the final step toward gaining European approval for full use in food contact applications. Lanxess expects to receive official approval from the European Commission very shortly. When this is granted, Mesamoll II would be one of the few plasticizers deemed suitable for use in food packaging in both the United States and the EU. However, the benefits aren't limited to just this specific market – the approval will also have a positive effect on the use of Mesamoll II in toys. Products from the Mesamoll range are particularly notable for their good resistance to saponification, outstanding solvating and migration properties, and compatibility with a wide range of polymers such as PVC, rubber and polyurethane.
Phthalate Plasticizers Covalently Bonded to PVC
Researchers at the Institute of Polymer Science & Technology in Madrid are developing technology to prevent potentially harmful plasticizers such as DEHP (DOP) from migrating from PVC. The advance could lead to a new generation of PVC plastics that are potentially safer than those now used in packaging, medical tubing, toys, and other products. The permanent plasticizer effect will also ensure PVC flexibility is maintained with the possibility of extending useful product life. The functionalized plasticizer DOP-SH [di(2-ethylhexyl) 4-mercaptophthalate] was developed with physiochemical properties similar to those of commercial DOP, but with an additional functional group able to establish a covalent bond to the polymeric backbone. The percentage of plasticizer that could be covalently linked to the PVC backbone was similar to plasticizer amounts usually commercially employed. The approach completely suppressed plasticizer migration. While the plasticizer efficiency of the novel plasticizers is less than conventional DEHP (DOP) the glass transition temperature of modified PVC is largely reduced and is around 0°C for the highest modified samples. This approach may open new ways to prepare flexible PVC with permanent plasticizer effect and zero migration.
Graphene Loaded Conductive Polymers
Vor-x from the Vorbeck Materials Group, a proprietary form of graphene containing functional groups, is a recent entry into the conductive additives market. The functionalized graphene allows compatibility to be ‘tuned’ to a specific matrix, or specific material properties to be enhanced. Vor-x graphene layers are entirely disassociated, and due to their wrinkled morphology individual sheets do not re-aggregate, ensuring good dispersion/handling, while providing the full performance advantages of graphene. Compounding Vor-x masterbatches into plastics is said to be much less difficult than CNT masterbatch material. The robust filler can take the high shear forces of a twin-screw extruder or mixer. Vorbeck has developed masterbatches in a wide range of thermoplastics, from polyolefins to PEEK. Vor-x is said to yield conductivities ‘well beyond surface anti-static and into the conductive regime.’ The material’s surface area can be theoretically as high as around 2,600 m2/g (meters square per gram) and in practice is as high as 1,700 m2/g. Electrical conductivity of natural rubber with 4% Vor-x compared with the same rubber loaded with 40% carbon black. Vorbeck and BASF are jointly developing graphene-based formulations and composite materials for conductive coatings and compounds, especially for the electronics industry.
Silver Based Antimicrobial Elastomer
StatSil elastomer developed by Momentive Performance Materials incorporates a silver-based antimicrobial additive into the base silicone elastomer using patent pending technology to provide antimicrobial protection. The product line offers excellent design flexibility. These antimicrobial elastomers are particularly suited to applications where controlling the growth of microbes in or on the human body is of concern in healthcare devices such as urinary catheters and intravenous components. Available as HCR (High Consistency Rubber) and LSR (Liquid Silicone Rubber) products, StatSil elastomers can be custom formulated to meet specific performance/processing requirements. The elastomers are available in hardnesses ranging in durometer from 3 to 80 shore A.
In Conclusion—Global Plastic Additives Market Drivers
Numerous additives are incorporated into thermoplastics to achieve a specific purpose during fabrication and/or service. Plastics could not deliver their performance without the addition of a broad range of polymer additives. The plastics additives global market of $46.3 B by year end 2014 has been growing at a CAGR (Compound Annual Growth Rate) of 4.5% over the last five years. Property modifiers have the largest share of the market, worth an estimated $22.8B by year end 2014. While overall growth for plastics additives is expected to average about 4% in the three major consuming areas (North America, Europe, Asia) growth is projected to be fastest in China and slightly negative for Japan. Plastics would not work without additives, but with them they are made safer, cleaner, tougher, and more colorful as well as more useful. Additives contribute to variable cost, but also reduce production costs and make products last longer, thereby helping to save money and conserve raw material reserves. Although used at only 5% to 7% in terms of weight or about 10% by cost, they provide immense benefits and have contributed significantly to the achievements of plastics.
Strongly tied to resins industry growth, demand for additives is also driven by unique performance and plastic product property requirements of the end-use consumer segments, particularly automotive, packaging, construction, medical, and consumer electronics. Specialty additives are one of the most dynamic segments of the plastics industry. These unique additives play a role in product development, reducing environmental impact, and gaining a competitive edge.
Advanced Plastic Additive Solution Suppliers
Company Trade name Website
ScentSational Technologies, LLC CompelAroma www.scentsationaltechnologies.com
Clariant Masterbatch CESA-Natura www.clariant.masterbatches.com
Sukano Products Ltd. Sukano www.sukano.com
PolyOne Corporation OnCap Bio www.polyone.com
Ampacet Corporation Ampacet www.ampacet.com
Toyota Tsusho Bio-PET www.taiamerica.com/
NEC Cardanol www.nec.com
NatureWorks LLC Ingeo www.natureworksllc.com
Teijin Ltd. Biofront www.teijin.com/
Croda Polymer Additives Solasorb www.croda.com
Nanophase Technologies Corp. NanoArc ATO www.nanophase.com
AGY Holdings Corporation S-1 Glass www.agy.com
Milliken Chemical Hyperform www.hyperformnucleatingagents.com
NaturalNano Inc. Pleximer www.naturalnano.com
FRX Polymers LLC FRX www.frxpolymers.com
Lanxess AG Mesamoll lanxess.com/en/corporate/home/
Institute of Polymer Science & Technology www.ictp.csic.es/ICTP2/en
Vorbeck Materials Group Vor-x www.vorbeck.com
Momentive StatSil www.momentive.com
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.