Aluminum hypophosphite

Aluminum hypophosphite decomposition temperature of 300 ℃, can be used for polypropylene PP, TPE / TPU wire and cable, PVC, PVC, potting adhesive materials such as halogen-free flame retardant, generally rarely used in nylon PA, polyethylene PE, polyester PET, rubber, PC and so on. The phosphorus content of aluminum hypophosphite is 40%, is second only to red phosphorus halogen-free inorganic phosphorus flame retardant, and aluminum diethylphosphonate is very different, the role of the use of almost different. Aluminum hypophosphite structural formula for Al (H2PO2) 3, CAS 7784-22-7 , solubility is 0.1g/100ml water. It has the characteristics of small particle size, uniform dispersion, no precipitation, small amount of addition, environmental protection and so on.

Basic information

English name: Aluminium hypophosphite; Phosphinicacid aluminumsalt; AHP

Chemical formula: Al(H2PO2)3

CAS NO.: 7784-22-7  

HS NO.: 28351000

EINECS No.: 479-150-8

Molecular weight: 221.96

Bulk density(20℃): 1.2 g/cm3

Hazardous grade: 4.1 category

Execution standard: HG/T4833-2015

Properties: white powder, slightly soluble in water

Export: tax rebate rate 0; need to apply for commodity inspection, dangerous package certificate

Quantity of 20 feet container: 12 tons; fumigation-free pallet or CP1-3 pallet.

Product index

Aluminum hypophosphite%≥98.0

P%≥40.0

Particle size(D50)μm:3-5

Particle size (D98)μm≤20

Whiteness≥98

Cl%≤0.005

Moisture w%≤0.5

PH: 3-5

1% decomposition temperature(℃)≥300

Flame retardant mechanism

1、Flame retardant mechanism when used alone

Aluminum hypophosphite produces a large number of non-combustible substances such as phospholipids and metaphosphates after exceeding the decomposition temperature, and at the same time, it absorbs the surface heat of the material and reduces the temperature of the ignition point, and the phosphoric acid ester covers the surface of the material and plays the role of isolating the oxygen and heat transfer. Phosphorus pentoxide in phosphate can capture hydrogen radicals (H・) and hydroxyl radicals (OH・) in the combustion reaction, thus interrupting the chain reaction of combustion.

2, Compound flame retardant mechanism

(1) Aluminum hypophosphite and MCA flame retardant can play a synergistic flame retardant effect of phosphorus and nitrogen after compounding, and the decomposition of MCA produces non-combustible gases such as ammonia NH3, nitrogen N2, etc. These gases can dilute the combustion area. These gases can dilute the oxygen concentration in the combustion area, so that combustion can not be sustained. At the same time, inert gases such as nitrogen can also form a layer of gas film on the surface of the polymer, hindering the transfer of heat and oxygen to the interior of the polymer, and play a role in isolation. In addition, the free radicals generated by the decomposition of nitrogen-containing compounds can also interact with the free radicals in the combustion reaction and inhibit the chain reaction of the free radicals, thus achieving the effect of flame retardancy. Ammonia NH3 and nitrogen N2 can promote the decomposition and volatilization of phosphorus-containing compounds, so that the flame retardant effect of phosphorus is more fully realized. Phosphate carbon layer can prevent ammonia NH3, nitrogen N2 gas from escaping too quickly, so that these gases accumulate under the carbon layer to form a higher pressure, thus diluting oxygen and flammable gases more effectively and enhancing the flame retardant effect.

Examples of application formulations

1, Polypropylene PP V-2 flame retardant formula

0.45% Aluminum Hypophosphite, 0.45% MHB, 0.1% Polybond wither.

2, TPE flexible cable flame retardant formulations

7-12% aluminum hypophosphite, 2% MCA

Precautions

1, aluminum hypophosphite in nylon PA, polyester PET, polycarbonate PC, ABS, polyethylene PE, rubber, wood, paper and other materials with poor flame retardant effect, is not suitable for use.

2, generally not suitable for magnesium hydroxide compounding, magnesium hydroxide high polarity, alkaline hydroxyl, will lead to decomposition of aluminum hypophosphite or reduce the flame retardant effect. Can be used with aluminum hydroxide, MHB, barium sulfate, talc, zinc borate and other compounding.

3, not used for a long time, there may be a small amount of moisture absorption phenomenon, need to be dried and used, otherwise affect the flame retardant effect.

4, in high temperature, especially the screw local shear temperature is too high, there will be a small amount of phosphine generated in some countries have restrictions on phosphine requirements need to be carefully considered for use.

Packaging, storage and transportation

25kg/bag, stored in dry and cool warehouse, avoiding fire, and stored separately from oxidizers and alkaline chemicals.

Aluminum hypophosphite is not resistant to alkali and oxidants, hydrophobicity is better, less water-soluble than ammonium polyphosphate APP, at present there is generally no coating or surface modification. Generally, coupling agent, lubricant and other additives can be added to improve the dispersion in the flame retardant material and reduce the phenomenon of precipitation and whitening.