Chemical properties

Chemical properties

Ⅰ. Chemical resistance

Table 11 shows the chemical resistance of TORAYCON™ non-reinforced grade (1401X06) after immersion for six months in different chemicals at room temperature. The study looked for changes in appearance, weight, dimensions and tensile strength. Table 12 provides qualitative comparisons with other engineering plastics.
TORAYCON™ is resistant to a broad range of chemicals. It exhibits resistance to inorganic chemicals, with the exception of concentrated sulfuric acid, concentrated hydrochloric acid and strong alkali. TORAYCON™ exhibits favorable resistance to organic chemicals—alcohols, ethers, aliphatic hydrocarbon and polymeric esters do not attack TORAYCON™. In particular, TORAYCON™ exhibits favorable resistance to gasoline and engine oils, making it a superb choice for automotive applications.
However, exposure to acetone, benzene or phenol causes swelling, as is the case with most other engineering plastics. For that reason, exercise caution in determining fitness for use.
Also note that ortho-chlorophenol and solvents combining ethane tetrachloride with phenol will cause TORAYCON™ to dissolve.

Table 11: Chemical resistance of TORAYCON™ non-reinforced grade (1401X06)
(after immersion for six months at room temperature)
Chemical Weight change (%) Dimensional change (%) Tensile strength retention (%) Appearance
Pure water +0.3 0 99 No change
3% sulfuric acid +0.3 +0.1 97
30% sulfuric acid +0.2 0 99
10% nitric acid +0.3 0 99
35% hydrochloric acid +0.5 0 - Some loss of glossiness
1% sodium hydroxide +0.3 +0.1 92
10% sodium hydroxide -0.1 +0.1 91
10% sodium chloride solution +0.3 0 95 No change
40% chromic anhydride -0.2 0 100
Methanol +1.3 +0.4 85
Ethanol +0.3 0 97
Acetone +3.9 +1.0 72
Methyl ethyl ketone +2.9 +0.5 77
Ethyl acetate +2.7 +0.4 80
Heptane +0.1 0 100
Cyclohexane 0 0 100
Glacial acetic acid +2.2 +0.2 78
Benzene +3.0 +0.5 70
Toluene +2.1 +0.3 85
5% phenol +9.6 +1.7 60 Yellowish discoloration and swelling
Carbon tetrachloride +0.6 0 100 No change
Dichloroethane +16.8 +4.7 50 Swelling
Dioctyl phthalate -0.2 0 100 No change
Dimethyl formamide +2.7 +0.3 80
1% surfactant +0.2 +0.1 99
Gasoline +0.2 +0.1 99
Olive oil 0 0 100
Kerosene 0 0 100
Heavy oil 0 0 100
Machine oil +0.1 +0.1 100
Table 12: Comparison of the chemical resistance of engineering plastics
Type of plastic PBT resin Modified PPO Polyacetal Polyamide Polycar-
bonate
(homopo-
lymer)
(copo-
lymer)
(6) (66)
Water absorption (%)* 0.08 0.07 0.25 0.22 1.32-1.90 1.5 0.15
Mild acid Safe Mostly safe Partly dangerous Mostly safe Safe
Strong acid Partly dangerous Mostly safe Dangerous Dangerous Partly dangerous
Mild alkali Mostly safe Mostly safe Partly dangerous Mostly safe Mostly safe Mostly safe
Strong alkali Dangerous Mostly safe Dangerous Mostly safe Mostly safe Dangerous
Active gas Mostly safe Immersed in chlorine gas Immersed in chlorine gas Mostly safe
Oil Safe Mostly safe Mostly safe Mostly safe Partly dangerous
Acetone Mostly safe Mostly safe Mostly safe Mostly safe Dangerous
Benzene Mostly safe Dangerous Mostly safe Safe Dangerous
Carbon tetra chloride Safe Dangerous Safe Mostly safe Dangerous
Alcohol Safe Mostly safe Safe Partly dangerous Partly dangerous
Ester Mostly safe Dangerous Mostly safe Safe Dangerous
Gasoline Safe Partly dangerous Safe Safe Dangerous
Solvent Ortho chloro phenol Carbon tetra chloride Special Phenol, formic acid, metacresol Methylene chloride, chloroform

*ASTM D570 (1/8" plate thickness, for 24 hours) All under no load.

Ⅱ. Stress cracking resistance

Table 13 shows the number of days before cracks appear on the surface of a dumbbell-shaped test specimen left to sit after deforming as shown in Figure 22.
TORAYCON™ non-reinforced grade (1401X06) indicates greater resistance to stress cracking than polyacetal.

Figure 22: Stress cracking resistance test (test specimen thickness: 3.2mm)

Figure 22: Stress cracking resistance test (test specimen thickness: 3.2mm)

Table 13: Stress cracking resistance
Test conditions Number of days until cracks appear
1401X06 Polyacetal
In air (145-150°C) 14-16 2-3
Engine oil (85-90°C) 28 or more 6

Ⅲ. Resistance to hot water

Figures 23 and 24 show the resistance to hot water of TORAYCON™ non-reinforced grade (1401X06) and glass-fiber reinforced grade (1101G-30). Similar to polycarbonate resin, the TORAYCON™ molecule contains an ester bond, which causes the molecule to hydrolyze after immersion in hot water for extended durations of time. The hydrolysis reduces the degree of polymerization, which in turn diminishes strength. So exercise caution before using TORAYCON™ in applications involving such conditions. That said, TORAYCON™ can withstand warm water of about 60°C for extended durations of time.
As shown in the section on heat-cycle resistance, TORAYCON™ can withstand exposure to hot water, if intermittent or short-lived.

  • Figure 23: Resistance to hot water of 1401X06 Figure 23: Resistance to hot water of 1401X06
  • Figure 24: Resistance to hot water of 1101G-30 Figure 24: Resistance to hot water of 1101G-30