Great Lakes launches stabilizers and flame retardants at K 2001.

Additives for Food Polymers Nov01

Great Lakes Chemical Corp introduced 12 new polymer additives for K 2001 - nine polymer stabilizer blends and three flame retardants.

The company launched two blends based on the antioxidant AlkanoxTM P24. Alkanox P-24 is a solid organo-phosphite antioxidant used as a long-term heat aging (LTHA) stabilizer in high end polyolefin applications, styrenics, PVC, polyesters, elastomers and adhesives. The blends make use of the company’s AnoxTM No Dust Blends technology and offer improved hydrolytic stability compared to performance of Alkanox P24 alone, the company says. Great Lakes has also expanded its range of hindered phenolic antioxidants by the addition of AnoxTM 330, an LTHA and processing stabilizer for polyolefin and other plastic applications. The company says this offers outstanding resistance to extraction in applications such as polyolefin water pipes, and very low impact on the dielec- tric constant in the production of polyolefin wire and cable. Hindered phenolic, and phosphite antioxidants have also been combined in two new synergistic blends, AnoxTM BB2777 and BB2888. Both contain Great Lakes’ antioxidant, Lowinox8’ 1790, launched last year, and the process stabilizer, AlkanoxTM 240. The low volatility of these components allows the new blends to be used at relatively high tempera- tures, the company says. The blends are effec- tive for process stabilization of a wide range of thermoplastics.

Two further ‘Anox’ blends - AnoxTM MDA01 1 and AnoxTM MDA085 - address the protection of polymers against the auto-oxidation process that can occur in the presence of transition metal ions from metal cable components or catalyst residues. The new blends are based upon the metal deactivator Lowinox’“’ MD 24 and the hin- dered phenolic antioxidant, AnoxTM 20: Anox MDA0 1 I is a 1: 1 blend and Anox MDA085 a 2: 1 blend of these components. Each is available in either powder or granular form.

Thermal and light stabilization of polyurethane was addressed by the launch of two high-per- formance liquid blends. Lowilite’” UV B 1260 is designed for applications with standard low fog- ging and thermal stability requirements, partic- ularly where superior UV protection is required, such as in outdoor integral skin applications. Lowilite’R‘ UV B121 1 is aimed at interior auto- motive applications, with very low fogging properties, excellent thermal protection, and good UV performance. The low viscosity of the blends makes make them easy to pump and they are readily miscible with common polyolefins in polyurethane applications. Automotive polyurethane applications, particularly hot- moulded foam seating, were also targeted with the introduction of a new halogen-free phos- phate ester flame retardant, Reofo@ NHP. A low viscosity liquid, which does not solidify above 0°C Reofo8 NHP mixes readily with polyolefins and TDI to yield well-structured foams with little discoloration or scorching. The foams exhibit excellent fogging and physical properties, which meet MVSS 302 test require- ments, Great Lakes says.

Finally, the company launched two non- diphenyl oxide (non-DPO) flame retardants. Firemaste? 550 is a non-scorch, phosphorus- bromine flame retardant for polyether and poly- ester polyurethane foams. It is a low viscosity liquid with good compatibility in polyurethane systems, where it disperses uniformly and pro- duces white foams with tine cell structure and good hand and physical properties. According to Great Lakes, it typically provides 30-50% lower compression set than other flame retardants and is particularly effective in CO, blown systems. Foams meet MVSS 302, CAL TB 117 parts A and D, as well as the more stringent UL94 HF- 1 specification. Firemaster” 2100 is a general purpose, non-DPO-based brominated flame retardant. Its high bromine content makes it a very efficient flame retardant option for a wide variety of polymers such as elastomers. styren- its, polyoletins and engineering polymers. Firemaster 2100 is a uniform white powder with excellent initial colour, suiting it for for- mulations requiring white or light-coloured products. Great Lakes says it also has excellent thermal and UV stability.

Contact: Great Lakes Chemical Carp, PO Box 2200, 1 Greut Lakes Boulevard, West Lqfa_vette, Indianapolis, IN 47906.5394, USA; tel: +I- 317-715-3000; .fax: +I-76.5-497-6316; URL: nww.pa.greatlakes.com

*************************************

BASF exhibits novelty blue pigment. Additives for Food Polymers Nov01

Described as a ‘trade-fair novelty’, BASF introduced a new low-warpage copper phthalocyanine blue pigment for colouring plastics at the K 200 1 show. Conventional copper phthalocyanine blues adversely affect the dimensional stability of PE-HD injection mouldings and hence their processing and functional properties. BASF claims its new Heliogen@ Blue K 6915 has no effect on the warpage of PE. The pigment, which is supplied as powder, consists of Cu phthalocyanine in the alpha form, stabi- lized by partial chlorination. Applications are large injection mouldings such as bottle crates, automotive parts, storage containers and trans- port containers.

In other recent BASF news, two units serving the coatings industry - Colorants for Coatings and Coatings Raw Materials - have been com- bined into a new operating sector ‘Performance Chemicals for Coatings’. The sector belongs in the Performance Chemicals operating division alongside Performance Chemicals for Plastics and Specialties. The new structure is aimed at meeting the changing requirements of the coat- ings industry more closely.

Contuct: BASF AC, D-67065 Ludwligshqfen, Gemany; tel: +49-62I-60-O;,fu.x: +49-621-60- 4252.5; e-mail: iqfo.sewice@ba$ug.de; URL. MWW: ba$com/pigment

*******************************

Global study to identify future opportunities for additives. Additives for Food Polymers Nov01

According to BRG Townsend, Inc, a consultancy firm based in Mount Olive, NJ, USA, suppliers in the USSl6 billion plastic additives industry are shifting their focus away from structural change towards product innovation. With the slowing pace of major industry consolidations, manufac- turers are concentrating on new products to exploit the dramatic shifts in the resin value chain and increased competition between polymers.

BRG is embarking on its fifth multi-client study of the global plastic additives business, which aims to identify new opportunities for 2002-2006 and evaluate their effect on the additives market- place. “Technology development and new growth markets are presenting opportunities that will impact the additives industry”, says Louis N. Kattas, Director - Performance Materials. “Significant new plastics technologies are result- ing in new applications that will provide prof- itable growth opportunities for selected plastic additives.” Kattas says that the plastics additives industry is also facing a shift in the form of its competition. Plastics are competing less against conventional materials and more against each other. For example, PVC is facing competition from polyolefins in pipe and automotive skin applications; acrylonitrile butadiene styrene and low-end engineering thermoplastics are being replaced by polypropylene; and the interplay continues between metallocene and conventional polyolefins in film and packaging uses.

In addition to analysis of regional and global consumption, market shares and forecasts for 15 additive families - from antiblocking agents to slip agents - Chemical Additives For Plastics ~ 2002 will include as a new feature a separate analysis of the present and future consumption of chemical additives in engineering thermo- plastics. Materials to be included are nylon, polycarbonate, PBT polyesters and polyacetal. BRG will also evaluate the market position, strengths, weaknesses and strategies of 15 key additive suppliers worldwide.

The report is scheduled for completion in April 2002 and will be available to subscribers for $16,500.

Contact: BRG Townsend, Inc, 500 Internationul Drive North, Mount Olive, NJ 07828, USA; tel. iI-973-347-5300, ,f&: +I-973-347-6466, URL: www.brgtownsend.com

****************************

Epoxy-based thermal stabilizer for PVC. Additives for Food Polymers Nov01

Polyvinylchloride (PVC) resins are very prone to thermal degradation by dehydrochlorination (the liberation of HCl) and oxidation. To prevent these reactions during high-temperature processing and normal use, the use of heat stabilizers is essential in order to maintain mechanical proper- ties and colour. In general these stabilizers act by scavenging liberated HCl, preventing autoaccel- eration of the dehydrochlorination reaction.

Table 1. Selected properties of PVC formulations with lead and epoxy-based thermal stabilizers

Formulation no. TBLS Epoxy (TGDDS) Tensile strength Elongation Induction YI after stabilizer (g) stabilizer (g) Pa) (W time (min) 40 mins 1 0.0 0.0 3.62 93 5.4 34.25 2 2.0 0.0 6.76 138 32.7 32.45 3 1.5 0.5 8.33 140 39.6 21.75 4 1.0 1.0 9.31 155 41.3 20.20 5 0.5 1.5 9.60 160 - 22.55 6 0.0 2.0 10.09 162 46.7 13.02

Lead-based thermal stabilizers such as tribasic lead sulphate (TBLS) have been widely used for PVC, but concerns over their toxicity have prompted concerted efforts to identify, and com- mercialize, non-metallic alternatives. In a study reported in Polymers & Polywer Composites (Vol. 9, No. 4. 2001, pp. 2833290) a tetrafunc- tional epoxy resin has been evaluated as a ther- mal stabilizer and its performance compared with TBLS. Stabilizing efficiency was assessed according to yellowness index, HCl liberation, UV absorption, induction time and changes in mechanical properties.

P.G.Patel and G.R.Patel of the Sophisticated Instrumentation Center for Applied Research and Testing, together with J.S.Parmar of Sardar Pate1 University, in Vallabh Vidyanagar, India, pre- pared the epoxy resin tetraglycidyl diamino- diphenylsulphone (TGDDS) by epoxidation from 4,4’-diaminodiphenylsulphone. Epoxy equiva- lent weight was determined to be 120 g.eq-‘, and number average molecular weight (by GPC) was 1022. A Brabender compounder, operating at 150°C was used to prepare a range of PVC sam- ples consisting of 30 g of PVC, 6 g of flame retar- dant (tricresyl phosphate), 6 g of filler (CaC03), 0.5 g of lubricant (stearic acid), 12 cm3 ofplasti- cizer (dioctylphthalate) and 2 g of TGDDS and/or TBLS thermal stabilizer (Table 1). A sam- ple with no stabilizer was also prepared as a con- trol. The change in torque during compounding was recorded and used to determine the fusion rate. The fusion rate was low when no stabilizer was used, increased in the presence of TBLS and was still higher with epoxy resin. A faster fusion rate allows a reduction in processing time, which results in less degradation of the PVC.

The compounded materials were compressed at 140°C into sheets of 222.5 mm thickness. After forming, the induction time, which is the time to the onset of HCl liberation, was determined using pH paper. As the amount of epoxy stabi- lizer increases from O-2 g, the induction time was found to increase almost eightfold, from 5.4 to about 45 minutes (Table 1). Induction time is an indicator of stabilizing efficiency, suggesting that the HCl absorption power of the epoxy resin is very promising.

It is difficult to prevent this initial release of HCl entirely at elevated temperatures. Any liberated HCI acts as an auto catalyst for further dehy- drochlorination, which is accompanied by the formation of unsaturated polyene groups. These groups show UV absorbance in the range 300- 400 nm. As the length of the polyene chains in the backbone increases the peak wavelength lengthens into the visible range, producing pro- gressive yellowing of the PVC.

In the present study, degradation of the PVC sam- ples aged in an oven at 180°C for up to 40 min- utes was followed by both UV spectroscopy and determination of the yellowness index (YI) using a special colour-matching computer. After aging the sample containing 2 g of TGDDS showed a UV absorption peak at 325 nm. As the amount of TGDDS decreased both the intensity and the wavelength of the UV absorption increased, to about 350 nm for the sample with no stabilizer. The YI was found to increase for all formulations with time, but after 40 mins was significantly lower for the epoxy-only formulation compared to both the TBLS and unstabilized samples (Table 1). In addition, mechanical properties such as tensile strength, elongation and surface hard- ness were all improved by the presence of the epoxy compound. The study therefore concludes that multi-functional epoxy resins are effective in stabilizing PVC against dehydrochlorination in both processing and use, comparing favourably with conventional TBLS stabilizers.

*********************************

PBDE Flame Retardants Earn Reprieve from European Commission. Additives for Food Polymers Oct01

Polybromodiphenyl ether (PBDE) flame retardants, sued in the production of polyurethane foam for furniture and upholstery, have been the subject of some debate recently between the European Parliamnent and the Commission. In response to the findings of an EU risk assessment, which recognized that penta-BDE poses a risk to the environment, is bioaccumulating, and hasbeen found in human breast-milk, the Commission proposed a directive in January this year banning the marketing and use of the chemical. In return, Parliament proposed amendments which would extend the scope of the proposed directive to include the phase-out of flame-retardants, octa-BDE and deca-BDE. The Commission rejected these amendments in early September on the grounds that the substances are the subject of ongoing risk assessments, due for completion at the end of this year. The Commission maintained that any future policy decisions on octa-BDE and deca-BDE should be based on the conslusions of these scientific evaluations. One amendment, which limits the future content of pent-BDE in octa-BDE to 0.1%, was accepted. The proposed directive will now recieve a second reading at the beginning of next year.

The European Bromated Flame Retardant Industry Panel (EBFRIP) welcomed the position taken by the Commission, sayinh that it "recognizes the need to take account of emerging EU risk assessments on octa-BDE and deca-BDE, as well as the importance of these flame retardants in terms of saving lives." EBFRIP also accepts the limit of 0.1% pent-BDE in octa-BDE.

EBFRIP. Av. E. Van Nieuwenhuyse 4, B-1160 Brussles: +32-2-676-7211; fax: +32-2-676-7301.

********************************

Alternative plasticizer for PVC could reduce incineration hazards. Additives for Food Polymers Oct01

The incineration of PVC materials, in waste dis- posal and in accidental fires, yields various chlorinated products. The precise composition of these products and the extent of the hazard they represent depends on the chemical struc- ture of the components of the PVC materials, and particularly on the type of plasticizer used. Plasticizers are typically present in high concen- trations in PVC materials.

A Russian study reported and Functional Polynzel:~ recently in Reactive (Vol. 48, Nos 1-3, 2001, pp. 209-213) measured the concentration of chlorinated polyaromatic hydrocarbons (PAHs) produced on combustion of PVC linoleum samples plasticized with two different materials: the conventional plasticizer dioctylph- thalate (DOP) and a new, cheaper alternative given the acronym EDOS, which is based on a mixture of 1,3 dioxane derivatives.

E.M. Gotlib and colleagues from Kazan State Technological University in Russia incinerated the linoleum samples in a specially constructed unit simulating combustion- at temperatures of 600-l 100°C. Total trapping of the incineration products was ensured by vacuum collection and absorption by a filter set. The trapped products were extracted using toluene at 100°C with addition of isotopically labelled analogues of PAHs as internal standards. The team analysed cleaned extracts by gas and liquid chromatogra- phy and mass spectrometry.

A strict protocol was followed to ensure correct identification of chlorinated dibenzo-p-dioxins (CDDs) and chlorinated dibenzofurans (CDFs), both highly toxic classes of organics that are deposited in the environment largely as a result of incinerating chlorine-containing polymers. CDDs chlorinated in positions 2,3,7,8 have the highest toxicity, the most hazardous being 2,3,7,8 tetrachloride dibenzo-p-dioxin (2,3,7,8TCDD). The toxicity of PAHs is thus usually expressed in ‘dioxin equivalents’ based on the toxicity of 2,3,7,8TCDD.

By measuring the concentrations of 17 of the most toxic CDDs and CDFs, it was established that total PAH concentration, in dioxin equiva- lents, in PVC linoleum plasticized with DOP is approximately twice as high as when EDOS is used as the plasticizer. Looking at specific molec- ular species, the concentration of phenantrene in DOP samples was twice that from EDOS-con- taining samples. Fluoroantene levels were 45 times higher, benzoantracene and chrizene con- centrations were approximately 100 times higher, and pyrene and antracene concentrations 200 and 250 times higher, respectively, in DOP samples. The study concludes that EDOS not only pro- vides good-quality flexible PVC decorative mate- rials at lower cost than DOP, but also significant- ly reduces the toxicity.