Výsledky projektu Funkcionalizované mikroporézní organické polymery pro adsorpční aplikace

Chain-growth polymerization of 1,4-diethynylbenzene into conjugated crosslinked polyacetylene-type poly(1,4-diethynylbenzene)s (PDEBs) is reported. While metathesis catalysts (WCl6/Ph4Sn, MoCl5 /Ph4Sn, Mo Schrock carbene) fail in this polymerization, insertion Rh catalysts ([Rh(nbd)acac], [Rh(nbd)Cl]2 ) provide microporous PDEBs in high yields. The Brunauer–Emmett–Teller (BET) surface, S(BET) , of PDEBs prepared with [Rh(nbd)acac] increases, in dependence on the polymerization solvent, in the order: THF << pentane < benzene < methanol < CH2Cl2. S(BET) further increases with both increasing monomer concentration and increasing polymerization temperature and reaction time, reaching a highest value of 1469 m2/g . In addition to micropores, PDEBs contain mesopores. The mesopore volume and average mesopore diameter increase with the time and the temperature of the polymerization up to 2.52 cm3/g and 22 nm (72 h, 75 °C). The post-polymerization thermal treatment of PDEB (280 °C) results in formation of new crosslinks and modifi cation of PDEB texture and sorption behavior manifested mainly by enhancement of H2 adsorption capacity up to 4.55 mmol/g (77 K, 750 Torr).

The π-conjugated micro/macroporous polyacetylene-type polyHIPE foams were synthesized for the first time by a chain-growth insertion polymerization of high internal phase emulsions (HIPEs). In the first step, the π-conjugated polyHIPE foams were prepared by polymerization of 1,3-diethynylbenzene HIPEs using [Rh(nbd)acac] complex as a catalyst. The π-conjugated polyHIPE foams consist of ethynylphenyl-substituted polyene main chains which are cross-linked by the 1,3-phenylene linkers. In the second step, the foams were chemically and thermally postmodified by applying the alkyne−azide cycloaddition reaction and the solvent free solid phase hyper-cross-linking at temperature of 280 °C. Thus, obtained polyacetylene-type polyHIPE foams exhibit hierarchically structured micro/macroporous morphology with sizes of the macropores and interconnecting pores of 3.4 ± 0.3 μm (or 4.8 ± 0.8 μm) and 0.96 μm (or 1.1 μm), respectively, wherein a substantial volume of micropores is also found within the macroporous walls as revealed by the calculations from the t-plots. The BET (Brunaer−Emmett−Teller) surface area of up to 110 and 380 m2/g was determined before and after solid phase hyper-cross-linking, respectively.

We report the synthesis of conjugated highly cross-linked polyacetylene-type networks with a high content of functional groups (–CH2OH, –NO2, –Ph2N, content up to 3.9 mmol/g) via a chain-growth copolymerization of either 1,4-diethynylbenzene or 4,4-diethynylbiphenyl with functionalized mono- and diethynylbenzenes. The backbone of the networks consists of substituted polyene main chains that are cross-linked by arylene links. The optimized combinations of comonomers in the feed provide functionalized networks with a Brunauer–Emmett–Teller specific surface area up to 667 m2/g and enhanced affinity for CO2 adsorption (compared to the non-functionalized hydrocarbon networks of the same type). The dependence of the specific surface area of the networks on the size and architecture of the comonomers used for the synthesis is discussed in the paper. The reported networks can be classified into the group of conjugated microporous polymers (CMPs). Contrary to the CMPs synthesized by step-growth couplings, significantly lower average comonomer functionality in the feed (f = 1.5 – 2.0) is sufficient for the high specific surface area to be achieved in the reported polyacetylene-type CMPs.

The π-conjugated micro/macroporous polyacetylene-type polyHIPE foams were synthesized for the first time by a chain-growth insertion polymerization of high internal phase emulsions (HIPEs). In the first step, the π-conjugated polyHIPE foams were prepared by polymerization of 1,3-diethynylbenzene HIPEs using [Rh(nbd)acac] complex as a catalyst. The π-conjugated polyHIPE foams consist of ethynylphenyl-substituted polyene main chains which are cross-linked by the 1,3-phenylene linkers. In the second step, the foams were chemically and thermally postmodified by applying the alkyne–azide cycloaddition reaction and the solvent free solid phase hyper-cross-linking at temperature of 280 °C. Thus, obtained polyacetylene-type polyHIPE foams exhibit hierarchically structured micro/macroporous morphology with sizes of the macropores and interconnecting pores of 3.4 ± 0.3 μm (or 4.8 ± 0.8 μm) and 0.96 μm (or 1.1 μm), respectively, wherein a substantial volume of micropores is also found within the macroporous walls as revealed by the calculations from the t-plots. The BET (Brunaer–Emmett–Teller) surface area of up to 110 and 380 m2 g–1 was determined before and after solid phase hyper-cross-linking, respectively.

Chain-growth polymerization of 1,4-diethynylbenzene into conjugated cross-linked polyacetylene-type poly(1,4-diethynylbenzene)s (PDEB) is reported. While metathesis catalysts (WCl6/Ph4Sn, MoCl5/Ph4Sn, Mo Schrock carbene) fail in this polymerization the insertion Rh catalysts ([Rh(nbd)acac], [Rh(nbd)Cl]2) provide microporous PDEBs in high yields. The BET (Brunaer-Emmett-Teller) surface, SBET, of PDEBs prepared with [Rh(nbd)acac] increases in dependence on the polymerization solvent in the order: THF << pentane < benzene < methanol < CH2Cl2. SBET further increases with increasing (i) monomer concentration and (ii) polymerization temperature reaching the highest value of ~1000 m2/g. In addition to micropores, PDEBs contain mesopores. The mesopore volume and average diameter increase with increasing temperature of polymerization up to 1.315 cm3/g and 14 nm (75 °C). The postpolymerization thermal treatment of PDEBs (280 °C) results in formation of new cross-links and modification of PDEBs texture and sorption behaviour manifested mainly by enhancement of H2 adsorption capacity up to 4.55 mmol/g (77 K, 750 torr).