Plastic with reduced sulfur uptake rate

A method for inhibiting the sulfur uptake in an organic, polymeric plastic which comprises adding a sulfur-uptake inhibiting amount of sterically hindered amine to said plastic, wherein the sterically hindered amine is at least one of the following amine compounds:

• I:
• oligomerized 2,2,4,4-tetramethyl-20-(oxiranyl-methyl)-7-oxa-3,20-diazadispiro{5.1.11.2} heneicosan-21-one,
• II:
• condensation product of 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triaz ine and 1,2-bis(3-aminopropylamino)ethane, or
• III:
• condensation product of 1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid.

A method for inhibiting the sulfur uptake of an organic, polymeric plastic, comprising the step of:

• adding to said plastic at least one of the following sterically hindered amine compounds:
• I:
• oligomerized 2,2,4,4-tetramethyl-20-(oxiranylmethyl)-7-oxa-3,20-diazadispiro›5.1.11.2!h eneicosan-21-one,
• II:
• condensation product of 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triaz ine and 1,2-bis(3-aminopropylamino)ethane, or
• III:
• condensation product of 1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid.