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We investigated radical copolymerization of styrene dimers [2,4-diphenyl-l-butene (STD)] and trimer [2,4,6-triphenyl-1-hexene (STT)], that are thermal degradation products of polystyrene, with maleic anhydride (MAn) at 60°C in THF or in bulk as a method for polymer recycling. The copolymerization of STD and MAn gave high-molecular-weight alternating copolymers [poly(STD-co-MAn)] (Mn = 10,000~30,000) in moderate yields (50~70%), while the copolymerization of STT and MAn gave alternating copolymers [poly(STT-co-MAn)] with a lower molecular weight (Mn = 6,000~17,000) and in lower yields (10~20%). The glass transition temperatures (Tg) of poly(STD-co-MAn) and poly(STD-co-MAn) were 211°C and 116°C, respectively. The hydrolysis of poly(STD-co-MAn) in water followed by sodium hydroxide addition gave water-soluble poly(STD-co-MAn) with pendant carboxylate groups [poly(STD-co-MAn)-COONa]. [ABSTRACT FROM AUTHOR]

Trifunctional polyacetal polyols with various main-chain structures were synthesized by polyaddition of hydroxyl-modified vinyl ethers (HBVE, HEVE, DEGV, CHMVE) in the presence of glycerine with an acid catalyst in tetrahydrofuran (THF) at 0°C for 4h. Crosslinked polyacetal polyurethane elastomers were synthesized by the reaction of polyacetal polyols with 2,4-tolylene diisocyanate at 120°C for 15 h. The obtained polyacetal polyurethane elastomers had glass-transition temperatures depending on their main-chain structure (- 58~10°C) and high thermal stability (274~312°C). The polyacetal polyurethane elastomers underwent smooth hydrolysis by treating them with aqueous acid in THF at room temperature to give the corresponding diol compounds for chemical recycling. [ABSTRACT FROM AUTHOR]

Aldehyde-terminated telechelic poly(2-adamantyl vinyl ether)s [poly(2-AdVE)s] were synthesized by water-based end-capping reaction of living poly(2-AdVE) with the bifunctional initiating system 1 [CH3CH(OCOCH3)-O(CH2)4O-CH(OCOCH3)CH3]/Et1.5AlCl1.5 in the presence of ethyl acetate in toluene at 0°C. The hydroxy-terminated telechelic poly(2-AdVE)s were synthesized by reduction of the terminal aldehyde groups with NaBH4. The obtained hydroxy-terminated telechelic polymers possess controlled molecular weights and narrow molecular weight distributions (sample I; Mn = 1,500, MwMn = 1.47, sample II; Mn = 3,200, M2/Mn = 1.48). ¹H NMR analysis showed that the resulting telechelic poly(2-AdVE)s had quantitative attachment of hydroxy terminals. Subsequent end-group transformation of hydroxy groups into acetate or urethane groups was possible. [ABSTRACT FROM AUTHOR]

The reaction of methacrylic acid with vinyl ethers of an epoxy group, 4-vinyloxybutyl glycidyl ether (VBGE) and cyclohexane dimethanol vinyl gtycidyl ether (CHDMVG), provided two types of triple functional monomers with a polymerizable vinyl group, a curable epoxy group, and an acid- sensitive degradable hemiacetal ester linkage (GBEM and GMCHMEM, respectively). GBEM and GMCHMEM were polymerized with 2,2'- azobisisobutyronitfile (AIBN) to give relatively high-molecular-weight soluble polymers. Poly(GBEM) and poly(GMCHMEM) were then cured through their pendant epoxy functions with amine curing agents at 100°C for 2h to produce the insoluble crosslinked poly(GBEM) and poly(GMCHMEM) thermosets. These cured epoxy resins were glassy and tough polymers and underwent degradation to give poly(methacrylic acid) via acid-catalyzed hydrolysis of the hemiacetal ester linkages in the polymers at room temperature. [ABSTRACT FROM AUTHOR]

Novel poly(vinyl ether)s with tetraethylene glycol and methacrylate side groups [poly(TetraEGMVE-VEEM)] were synthesized by the copolymerization of TetraEGMVE with VEEM. The free-standing membranes of poly(TetraEGMVE-VEEM)s were prepared by thermal crosslinking between the methacrylate units. Membranes of poly(TetraEGMVE-VEEM) with 2:1 composition ratio showed high CO2 permeability and CO2/N2 selectivity, whose PCO2 and PCO2/PN2 were 250 barrer and 52, respectively. The PCO2 of membranes of poly(TetraEGMVE-VEEM) with 4:1 composition ratio was 320 barrer, which is larger than that with 2:1 composition ratio. This difference is caused by the number of crosslinking points in the polymer matrix. The CO2 permeability of poly(TetraEGMVE-VEEM) is higher than that of poly(vinyl ether) having diethylene glycols as a side chain. This high permeability originates from the high diffusivity of CO2 in the membranes. [ABSTRACT FROM AUTHOR]

Gas permeability of ionene polymers (PTIs) containing poly(tetrahydrofuran) [PTHF] soft-segment blocks (the molecular weight of PTHF block: 1100 and 2300) and viologen hard ionic segments (counter anion: Cl-, Br-, and I-) were investigated. The gas permeability coefficients of carbon dioxide (PCO2) and the CO2 and N2 separation factor (PCO2/PN2) of PTI having the 2300-PTHF block molecular weight and Cl- counter anion were 201 barrer and 30, respectively, indicating that PTI is a good candidate for CO2 separation membrane polymer. [ABSTRACT FROM AUTHOR]