LOTNOX 9228(ANTIOXIDANT 9228) (CAS:154862-43-8)

LOTNOX 9228(ANTIOXIDANT 9228)

Lotnox 9228 belongs to the family of spiro  phosphite antioxidants which are known for their high phosphorous content and notable efficiency compared to other phosphite-based antioxidant families. However, does not suffer from the intrinsic weakness of low hydrolytic stability caused by the spiro structure. At ambient temperature, Lotnox 9228 maintains its free flowing properties even after being exposed to a highly humid environment (> 80%) for more than 30 days.

Furthermore, the large molecular weight and unique structure makes the molecule very heat stable and it holds the record for thermal stability amongst the commercial phosphite antioxidants.

Like the other phosphite antioxidants, Lotsorb 988 acts as a secondary antioxidant by quenching the hydroperoxide during the auto-oxidation cycle and retards the degradation associated with color development in particular. When used in engineering plastics such as polyester and nylon, it demonstrates excellent color protection during plastics compounding to an extent unmatched by other phosphite antioxidants even at excess dosage, see Figures 3 and 4.

This outstanding efficiency cannot be explained simply by high thermal stability, low molten color (see Figure 2) and high phosphorous content. A not yet clearly understood mechanism transforming the dark color intermediates associated with the oxidized form of the hindered phenolic-based primary antioxidants back to a low color form could also be a contributor to the efficiency.

Lotnox 9228 also adds value to the non-engineering plastics such as PP, PVC, PS, POM, ABS, PMMA, etc, by stabilizing their physical and mechanical properties to a very high degree.

CAS No.:[154862-43-8]

Structure

Chemical name

Bis (2,4-dicumylphenyl) pentaerythritoldiphosphite

Physical Data

Odor: Odorless

Bulk density : 0.75 g/mL

pH : 7.66

TGA (10% loss): 340 °C

Phosphorus content: 7.3%

Solubility (g in 100ml solvent @ 20 °C)

Acetone: < 0.10

Ethyl acetate: < 0.10

Hexane: < 0.10

Dichloromethane : 0.80

Toluene: 0.13

Cyclohexane: < 0.10

Mineral oil: < 0.01

Acetonitrile: < 0.10

Methanol: < 0.10

Isopropanol: < 0.10

Water: < 0.10

Specification

Appearance: White free flowing powder

2,4-DCP (%): 1 % max.

Acid value: 3 mgKOH/g max.

Tributylamine: 2,000 ppm max.

Color, WI: 82.0 min.

Volatile (%): 0.5% max.

Melting point: 225-246 °C

Fig 1. Typical thermogravimetric analysis (TGA) diagram

Fig 2. Molten color

(1) Tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenyldiphosphonite

(2) AN 604 : Bis(2,4-di-tert-butylphenyl)pentaerythritoldiphosphite

(3) Lotnox 9228

(4) Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol-di-phosphite

(5) 2,2',2''-Nitrilo[triethyl tris(3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl-2,2'-diyl)phosphite]

Fig 3. Color stability of PET – multi extrusions at 280 °C

AO-1: 500ppm AN 1010;

AO-2: 500ppm AN 10 10 + 1,500 ppm AN 168;

AO-3: 500ppm AN 1010 + 1,500 ppm Lotnox 9228

Fig 4. Color stability of PA66 – compounding once at 280 °C

AO-4: 500ppm MD-1098 + 1,500 ppm

AO-5: 500ppm MD-1098 + 6,000 ppm

AO-6: 500ppm MD-1098 + 1,500 ppm Lotnox 988;

AO-7: 500ppm MD-1098 + 3,000 ppm AN 168 Lotnox 988;

Fig 5. Differential scanning calorimetry (DSC)

Packaging and Handling

Packaging: 25Kg/Carton

Store the product in a cool, dry, well-ventilated area away from incompatible materials. Unless stated, proper storage will permit usage of the product for 12 months from the manufacture date. For additional handling and toxicological information, consult the Material Safety Data Sheet.