The world’s largest plastics show next month in Dusseldorf will highlight an unusual mix of new polymer additives, including some based on novel chemistries that reportedly set new levels of performance. These include PP clarifying and nucleating agents, an anti-scratch-and-mar additive for PP, a stabilizer for nanocomposites, and “all-natural” color and additive masterbatches for biopolymers.
Also being introduced are a “dryable” foaming agent for polycarbonate, a high-efficiency impact modifier for PVC and CPVC, additive packages for wood-plastic composites (WPCs), and mold releases for engineering thermoplastics. Other news includes specialty fillers, non-halogen flame retardants, PVC processing aids, and new black pigments for soft PVC, PUR, and UP resins.
Ciba Specialty Chemicals is launching a clarifier/nucleant for PP that is said to be based on a new chemistry that allows for major cost reduction. Irgaclear XT-386 is based on trisamides rather than sorbitol. Use levels to reduce haze and increase clarity of PP are said to be less than 10% of those for conventional products—i.e.,150 ppm vs. 2000 ppm. It is said to be suited to random copolymers for thin-wall injection molding of food containers and stretch-blow molding of bottles. Industrial trials with DVDs and bottles have shown that addition of XT-386 results in significantly shorter cycles.
New levels of clarity in PP resins are said to be achieved with a next-generation clarifier that is being introduced by Milliken Chemical Co. Compared to existing products, Millad NX8000 is said to offer dramatic haze reduction along with good heat and impact resistance—and it is cost-effective as well, according to Milliken. This clarifier is derived from a new class of molecules based on nonitol.
A proprietary, “first-of-a-kind” additive reportedly provides excellent scratch and mar resistance to PP and TPO auto exterior and interior parts ranging from bumpers to instrument and door panels. Ciba’s Irgasuf SR 100 can be added during injection molding as an alternative to using maleic anhydride-grafted PP. In the Five-Finger Scratch Test, samples containing this unique additive showed excellent visual improvements in scratch and mar performance up to 15N, while also boosting impact performance. Typical use levels are 1% to 3%.
Antioxidant for nanos
Ciba is also introducing a reportedly unique stabilizer for nanoclay-based nanocomposites. Irgatec NC 66 is a proprietary blend of antioxidants and other ingredients that reportedly works on the different elements of a nanocomposite that are known to increase risk of degradation, including the nanoclay, compatibilizer, and impact modifier. This additive package is said to improve processing stability, enable hotter and faster processing, reduce yellowing during aging, enhance long-term heat and light stability, and reduce odor during processing.
Additives for biopolymers
What is possibly the first commercial introduction of “all-natural” color and additive masterbatches made entirely from renewable resources is aimed at “green” packaging and consumer products made from biopolymers. Based on natural materials like flowers, Renol-natur color concentrates and Cesa-natur additive concentrates from Clariant Masterbatches are biodegradable and designed for use with PLA (polylactic acid), PHA (polyhydroxyalkanoate), PHB (polyhydroxybutyrate) and starch-based resins. Available colors include red, orange, yellow, and green. Blue is in final stages of development, and the colors can be combined to make additional shades and tones. These colorants are described as “very earthy and organic looking,” and some are said to have excellent clarity. However, their lightfastness is not as high as that of conventional non-renewable pigments, so they are not suitable for all applications. Although biopolymers have been used mainly in packaging so far, manufacturers of consumer durables, such as phones, music players, and laptops are also very interested, according to Clariant.
‘Dryable’ foaming agent
A new high-temperature foaming-agent masterbatch for polycarbonate reportedly can be preblended with virgin PC and then dried, rather than having to be dried separately at lower temperature, like competing products. New Safoam NPC-20 from Reedy International Corp. is an endothermic type that generates CO2 gas and reportedly does not degrade the PC resin.
Toughener for PVC, CPVC
Arkema is launching an addition to its line of Clearstrength MBS impact modifiers for use in rigid PVC and CPVC injection molding, sheet, and profiles. Opaque, high-efficiency Clearstrength 859 reportedly imparts up to 20% higher impact strength than other opaque MBS modifiers while maintaining a wide processing window. The increased efficiency could permit cost savings, Arkema says.
Additives for WPC
Reedy International Corp., will introduce new additive packages for wood-plastic composites based on HDPE, PP and PVC. Among them is Saftec AS, a heat stabilizer that is applied to the wood fiber prior to processing, which facilitates processing of highly filled composites at higher temperatures without oxidation or charring. Other claimed benefits are enhanced color stability, reduced water absorption, and prevention of mold growth. It is also said to act as a processing aid, allowing for higher extrusion rates with improved tensile and flexural strength and surface characteristics.
Reedy’s new Sekur is an aqueous liquid suspension of high-molecular-weight PE that adheres to wood and can be applied to the wood-fiber/plastic blend prior to processing. Dyes can be diluted in Sekur and used to color the wood. It is also said to improve dispersion of wood fibers.
The two foregoing products are available together in one package as Saftec ASC-25-Sekur and ASCZ-25-Sekur. These are the new Saftec heat stabilizer coated with the Sekur water-based PE. The packages are said to prevent water absorption by WPCs. ASCZ-25 contains a special dispersion aid that reportedly results in improved tensile properties and promotes crosslinking for added melt strength.
Reedy’s Safoam RIC/FP is a new 100%-active powder form of the company’s low-temperature endothermic chemical nucleating and blowing agent. It is also available as RIC50/FP masterbatch with 50% active ingredient.
Axel Plastics Research Laboratories will highlight two new processing aids and mold releases for engineering resins, offered as free-flowing powders or as 100%-active pellets. MoldWiz INT-35UPC, a blend of organic fatty amides and glycerides, is said to offer improved release of PC and PC/ABS blends. Recent tests show that a 0.3% addition to a PC/ABS resin required 11% less force to eject a molded part than an identical part without the additive. The product is also said to give a more consistent surface finish.
MoldWiz INT-38HM is a silicone-free organic formulation suitable for nylon, styrenics, PPS, PBT copolymers, and a variety of other engineering resins. A field test showed that 0.5% of INT-38HM pellet in PPS resolved sticking problems and high reject and return costs for PPS electrical connectors. The additive reportedly allowed the molder to reduce process temperatures by 30º F while significantly enhancing resin flow, which permitted the multi-cavity mold to fill easily with less packing pressure.
Other new additives
Nyco Minerals is introducing two new specialty wollastonite fillers. Elektra-Stat is a conductive reinforcing grade, said to be the first of its kind, designed to complement or replace conductive carbon black or carbon fiber. Elektra-Stat is said to be competitively priced and readily available.
Aspect 3000 is a wollastonite for engineered alloys and blends, where it reportedly combines high stiffness with good ductility, improved HDT, and low CLTE compared with other minerals. The target is thin-wall molding.
Ciba Specialty Chemicals is introducing a melamine polyphosphate flame retardant intended as a component of halogen-free FR formulations. Melapur 200 is said to work well with other non-halogen FR additives in many resin systems, particularly nylon, epoxy, and TPU. It is reportedly heat stable during processing, maintains electrical and other properties, and can help achieve UL 94V-0 performance in printed circuit boards and various other IT and telecommunications equipment.
Degussa is launching Nerox, a comprehensive range of pigment blacks for liquid components of soft PVC, PUR, and unsaturated polyester resins. Also new from Degussa are PVC processing aids—Decalan 40 F for foams and Decalan 75 F for sheet and film. The latter boasts an external lubricating effect.