CURING OF UNSATURATED POLYESTER RESINS
> Cold curing peroxides Luperox® K1
Medium activity MEKP. A standard generalpurpose hardener for a variety of ambienttemperature applications. Low hydrogenperoxide content makes K1 ideal for usein gel coats. Luperox® K10
Low activity MEKP. Gives fast gel and curetime for a variety of ortho and isophthalicresin systems. Luperox® K12
Low activity MEKP that gives long gel timesin a wide variety of ortho and isophthalic resinsystems. Particularly suitable during the warmseason and for very large moulded pieces. Suitable for fast curing of vinyl ester resinsto obtain blister free laminates. Luperox® K2
MIKP for short curing cycles at medium andhigh temperatures from 65°C to 120°C evenwithout cobalt accelerator. Mostly used forthe manufacture of flat and corrugated sheetsin continuous processes. Luperox® K21
As Luperox® K2 but longer pot life when used with a cobalt accelerator. Luperox® K3
Rapid propagation from gel to exothermic peak in many resin systems. This fast curing and heat dissipation are particularly useful for continuous and semi continuous production processes. Its high activity makes it suitable during cold season. Luperox® K3 / cobalt is the only alternative to a benzoyl peroxide / amine system if colour stability as well as fast curing is required. It is not recommended for gel coats and vinyl ester resins. Luperox® K4CE Plasticizer
High activity cyclohexanone peroxide, it givesrelatively short gel times and gradual curingwith a low peak temperature. This productensures curing of even thick wall pieces withoutstress or crack formation. Luperox® Z11
Ketone peroxides blends for technologies requiring a comparable gel time with Luperox® K1 but faster curing times with peak temperatures Luperox® Z13
lower than those obtained with Luperox® K3. In a wide variety of resins, Luperox® Z13 has a slightly higher activity than Luperox® Z11. Luperox® Z19
Special blend of ketone peroxide that allowcontrolled curing at temperatures up to morethan 60 oC. This blend is suitable for continuousand semi-continuous processes. * Tests were carried out at 21 oC in 50 g of a standard orthophthalic resin, with 2% of each peroxides and 90 ppm of cobalt accelerator (1% metal content solution).
> Hot curing peroxides Luperox® 231M50
As Luperox® P, but lower molding temperatures. Used when heavy metals are present which affect the pot life of peresters peroxides. Luperox® 231P50 Luperox® 331M50 Luperox® 331P50 Luperox® P
For hot press molding between 130 - 160 oC.
Suitable when high gloss surfaces are required. Luperox® DP10
Typical molding temperature of 60 - 100°C with
cobalt accelerator. A substitute for Luperox® 26 where storage and transport of this peroxide present a problem. Especially suitable for polymer concrete and artificial marble process system. Luperox® 26
Hot curing above 60°C. Requires transport and storage below 15°C. Luperox® 26SR90
Activity like Luperox 26, but longer potlife in prepregs. Luperox® TBEC
For hot press molding between 130 - 160°C. Luperox® MC
Activity similar to Luperox TBEC, but it gives lower residual styrene in the final article.
> Benzoyl peroxides Luperox® A75
Benzoyl peroxide is used to cure both at room
temperature and medium temperatures. At ambient temperatures it requires the useof tertiary aromatic amines as activator. Luperox® ANS50
The peroxide amines system gives quick gel
and cure times and it is mailnly used for polyesterrepair putties and mine bolts. In hot press molding, benzoyl peroxide can be
used alone and gives quick cycles at 100 - 120°C.
Pastes are available in different colours. Luperox® ANS50N * Tests made in a generic UPR formulation, containing fillers but no inhibitor, thickening agent or glass fibre. 1,5 phr of each peroxide added for all tests.Trials have been carried out on a “SMC Technology” press (thickness of parts: 4mm for all trials).Safe handling of organic peroxides
Observe exact storage temperature indicated on product label.
Keep away from sources of ignition and heat. Store in a cool dark place - well separated from accelerators 2 andother flammable material. Danger of explosion: never mix peroxides and accelerators together; 3 add each component separately to the resin.
Store peroxides in original containers. Contact with rust, ash, dirt, accelerators and many other chemicals can cause violent 4 decompositions.
Even in diluted form peroxides have a corrosive effect on the skin and eyes. Always wear gloves and protective goggles 5 when handlingperoxides. Smoking and naked flames strictly prohibited in work and storage areas! In case of accidents: first aid EYES: In case of eye contact, rinse immediately with large quantities of water for at least 10-15 minutes. Contact an ophthalmologist immediately. INGESTION: In case of accidental swallowing, do not induce vomiting. Administer water in small sips and charcoal tablets in addition. Call a doctor immediately. SKIN • BODY: Remove soaked clothes immediately. Wash skin with plenty of water and cover skin with sterilized bandages. Seek medical advice. SPILLAGE: If peroxide is spilled, absorb with inert material e.g. Vermiculite or clean sand immediately and destroy in accordance with local regulations. FIRE: Suitable extinguishers are waterspray and foam. In case of large fires: Fight fire from safe distance (10 -15 m). Cool containers/tanks with water spray. Call fire brigade immediately. Consult Safety Data Sheets before handling organic peroxides A global chemical player, Arkema combines 3 related and integrated business segments: Vinyl Products, Industrial Chemicals, and Performance Products. Present in over 40 countries with 18400 employees, Arkema achieves sales of 5.7 billion euros (2005). With its research centers in France, the United States and Japan, and internationally recognized brands, Arkema holds leadership positions in its principal markets.
The information contained in this document is based on trials carried out by our Research Centres and data selected from the literature, but shall in no event be heldto constitute or imply any warranty, undertaking, express or implied commitment from our part. Our formal specifications define the limit of our commitment. No liability whatsoever can be accepted by Arkema with regard to the handling, processing or use of the product or products concerned which must in all cases
be employed in accordance with all relevant laws and/or regulations in force in the country or countries concerned.
92800 Puteaux - FranceTél. : 33 (0)1 49 00 80 80
Arkema - société anonyme au capital de 604
Treatment of Menorrhagia BARBARA S. APGAR, MD, MS, AMANDA H. KAUFMAN, MD, UCHE GEORGE-NWOGU, MD, and ANNE KITTENDORF, MD, University of Michigan Medical Center, Ann Arbor, Michigan Menorrhagia is defined as excessive uterine bleeding occurring at regular intervals or prolonged uterine bleeding lasting more than seven days. The classic definition of menorrhagia (i.e., greater than 80 mL of
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