Application of antioxidant in polypropylene (PP)

2022/06/16

Polypropylene (PP) is a polymer of propylene by addition polymerization. Chemical formula is (C3H6) N, density 0.89 ~ 0.91g/cm3, [1] flammable, melting point 189, softening at about 155, using temperature range -30 ~ 140[2].

 

Polypropylene is a kind of excellent thermoplastic synthetic resin, it is a colorless translucent thermoplastic lightweight universal plastic. With chemical resistance, heat resistance, electrical insulation, high strength mechanical properties and good high wear-resisting processing properties, so in machinery, automobile, electronic appliances, construction, textile, packaging, agriculture, forestry, fisheries and food industry and many other fields have been widely developed and applied. And because of its plasticity, polypropylene is gradually replacing wooden products, and its high strength, toughness and wear resistance have gradually replaced the mechanical function of metal. In addition, polypropylene has good grafting and composite functions, and has a huge application space in concrete, textile, packaging and agriculture, forestry and fisheries

 

However, the product has good thermal stability in the absence of oxygen. But it is very sensitive to oxidation, so it cannot be used properly without proper stabilization. Therefore, after the polymerization of polypropylene, antioxidants are generally added in the granulation stage. In fact, the application of antioxidant in addition to phenolic antioxidant phosphite antioxidant, the combination of the two will achieve a good synergistic effect

 

Such as the following two:

 

Phenolic antioxidant 1010

 

CHEMICAL COMPONENT

COMPONENT

Pentaerythritoltetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate)

CAS

6683-19-8

Molecular

C73H108O12

M.W

1177.60


 

 

SPECIFICATION AND PHYSICAL PROPERTIES

 

TEST

UNIT

SPECIFICATION

APPEARANCE


WHITE POWDER

MAIN CONTENT

%

94.00MIN

EFFECTIVE COMPONENTS

%

98.00MIN

VOLATILES

%

0.50MAX

ASH

%

0.10MAX

MELTING POINT

110.00-125.00

CLARITY OF SOLUTION


CLEAR

TRANSMITTANCE



425nm

%

96.00MIN

500nm

%

98.00MIN

 

phosphite antioxidant168

 

CHEMICAL COMPONENT

COMPONENT

2,4-bis(1,1-dimethylethyl)-phenophosphite(3:1)

CAS

31570-04-4

Molecular

C42H63O3P

M.W

646.92


 

 

SPECIFICATION AND PHYSICAL PROPERTIES

 

TEST

UNIT

SPECIFICATION

APPEARANCE


WHITE CRYSTALINE POWDER

CONTENT

%

99.00MIN

VOLATILES

%

0.30MAX

MELTING POINT

183.00-187.00

CLARITY


CLEAR

TRANSMITTANCE



425nm

%

96.00MIN

500nm

%

98.00MIN

CONTENT OF DTBP

%

0.20MAX

ACIDITY

mgKOH/g

0.25MAX

HYDROLYZATION

h

14MIN