Additives (K 2001 Preview)

New flame retardants

Great Lakes Chemical Corp.’s Polymer Additives Div., Lafayette, Ind., is showcasing three new products:

• Reogard 1000 is a non-halogen, phosphorus-containing blend for injection molded PP consumer electronics. Its intumescent action suppresses smoke and heat release. It is also melt blendable and has low tendency to absorb moisture that can adversely affect electrical properties. Use levels are 17-22 phr to achieve UL 94V-0 in PP homopolymer and 25-30 phr in PP copolymer.
• A patented phosphorus-bromine additive (as-yet unnamed) for flexible PUR furniture foams is intended as an alternative for the company’s workhorse BE60S brominated diphenyl ether, which has raised environmental/health concerns in Europe. The new product has comparable use levels—8-15 phr, depending on foam density—and reportedly produces foam that meets California’s Cal 117 specifications. It is said to result in low compression set and to be particularly effective in HR foams.
• A low-fogging, non-halogen FR specifically for use in hot-molded, TDI-based PUR automotive foams is aimed primarily at the European market. It is an alternative to tris-dichloropropyl phosphate (TDCP) and is comparable in cost. Typical use levels are 4 to 5 phr.

Clariant Corp.’s Pigments and Additives Div. (U.S. headquarters in Charlotte, N.C.) will highlight newly optimized products from two halogen-free FR product lines:

• Exolit AP 75X is a product group based on ammonium polyphosphate with nitrogen-containing synergists. For use in polyolefins, grades AP 750, AP 751, and AP752 were optimized for electrical/electronic uses. They are said to provide good flow and UL 94V-0 and 5V performance.
• Exolit RP is an extensive product line based on red phosphorus, including powder grades, dispersions, and concentrates in phenolic resins, nylon 6, and LDPE. Newly optimized products from the Exolit RP 69X range are said to be the most effective for nylon 66. Improved concentrates of these products for nylon electrical/electronics applications are also being introduced. They are said to confer high tracking resistance and very good mechanical properties.

Albemarle Corp., Baton Rouge, La., will showcase its extended line of flame retardants resulting from its recent acquisition of Martinswerk GmbH in Germany. The latter’s Martinal alumina trihydrate and Magnifin magnesium hydroxide flame retardants are now offered in the U.S. as complements to Albemarle’s brominated and phosphorus-based products and antimony synergists.

 

New additives for PVC

Dover Chemical Corp., Dover, Ohio, will highlight its patent-pending complex phosphite esters, which are billed as a new approach to stabilizing flexible PVC. Dover’s PhosBooster can partially or fully replace conventional mixed-metal stabilizers. Compared with the conventional phosphites used in BaZn and BaCd systems, PhosBooster products reportedly reduce VOCs, plate-out, and moisture blush. Also, PhosBooster’s lower initial color can reduce pigment costs, particularly for clear and light colors.

Rohm and Haas Co., Philadelphia, will introduce a new all-acrylic impact modifier for vinyl siding, windows, and fence profiles. Paraloid KM-348 reportedly matches the performance of CPE or other acrylic modifiers even when used at 20% lower levels. What’s more, KM-348 reportedly reduces melt temperature and viscosity, so it can boost throughput rate by 10-25% relative to formulations containing other impact modifiers.

 

Toughener for PP

Basell Polyolefins, Wilmington, Del., says its new Hifax 7320 PP-copolymer impact modifier offers PP and TPO compounders more flexibility in balancing toughness, stiffness, and shrinkage characteristics, along with economics. The modifier is intended to compete with EPDM, EPR, and plastomers. Compared with Basell’s Hifax CA 138 A, the new grade achieves better low-temperature impact strength at 30-35% lower addition levels. It also boasts better impact/stiffness balance and lower gloss.

 

The latest antioxidants

Great Lakes will feature the newest additions to its portfolio of phenolic phosphite antioxidants. One of these is Anox 330, equivalent to Albemarle’s Ethanox 330. It is a high-performance, hindered phenolic for PP and HDPE pipe, film, tape, wire, and cable.

Several of Great Lakes’ No-Dust Blends (NDBs) incorporating Anox 330 will be featured at K 2001, including two new liquid blends with a light stabilizer that are said to offer low fogging in PUR integral-skin foams for auto interiors.

Also to be featured is Great Lakes’ recently introduced Alkanox P24 high-performance phosphite. It boasts outstanding color protection in polyolefin and polycarbonate films and fibers. A pentaerythritol diphosphite with a melting point of 347 F, it is said to be similar to Ultranox P626 from GE Specialty Chemicals. Long-term heat stabilization is provided at use levels of 0.05-0.1%. When incorporated in NDBs, P24 is said to offer improved hydrolytic stability.

Another new entry from Great Lakes is Lowinox 1790, a specialty hindered phenolic antioxidant for HDPE rotomolding and PUR fiber. It is said to contribute less color than other phenolics and to provide excellent gas-fading and extraction resistance.

Also new is Great Lakes’ Lowinox MD 24, a hydrazine phenolic copper deactivator for polyolefin wire and cable.

New from Dover Chemical are Dovernox D-Blends of primary antioxidants combined with its patented Doverphos S-9228 phosphite. They are aimed at ABS, acrylic, elastomers, nylon, PBT, PET, PC, PE, PP, PS, PUR, and PVC. Doverphos S-9228 is a high-molecular-weight, low-volatility phosphite that reportedly provides superior thermal stability and protection against discoloration, as well as extremely good hydrolytic stability. It has food-contact approval in several countries.