The β₯-radiation-induced graft copolymerization of 2,2,6,6-tetramethyl-4piperidinyl methacrylate (TMPM) onto polypropylene (PP) was investigated using a simultaneous-irradiation technique. The effects of solvents, atmospheres, dose, and monomer concentration on the percent of grafting were studied. T
Effect of penta- and tetramethyl HALS on the radiation resistance of polypropylene
β Scribed by Huiliang Wang; Wenxiu Chen
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 203 KB
- Volume
- 69
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
β¦ Synopsis
2,2,6,6-Tetramethyl-4-piperidinyl methacrylate (TMPM), a new pentamethyl HALS 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate (PMPM), their homopolymers (PTMPM and PPMPM), and their copolymers, [i.e., TMPM or PMPM copolymerized with monomers methyl methacrylate (MMA), methacrylic acid (MAA), acrylic acid (AA), and styrene (St) separately] were synthesized. PMPM shows an extremely excellent stabilizing effectiveness on improving the radiation resistance of polypropylene (PP) in comparison with other low molecular weight (LMW) HALS or polymeric HALS. Polymeric HALS shows a much higher thermal stability and better extraction resistance than that of LMW HALS. It is found that the Eb values of the PP-added pentamethyl HALS series are higher than those of PP with the corresponding tetramethyl HALS series at a given irradiation dose. A conclusion can be drawn that the pentamethyl HALS series has a higher stabilizing effectiveness than that of the tetramethyl HALS series.
π SIMILAR VOLUMES
The effects of the molecular weight of polypropylene, nucleating agent, and types of stabilizers on the grafting of methylmethacrylate onto polypropylene sheets were examined. The oxidation of polypropylene sheet surfaces exposed to air after irradiation was studied by measuring survey scan spectra
Novel fluorinated methacrylate polymers were synthesized. The purpose was to produce polymers with low refractive indices and increased resistance to optical radiation damage. Six different fluorinated substituents were appended on the monomer before polymerization. Optical-quality samples were prep