New Host Polymeric Framework and Related Polar Guest Cocrystals

Abstract

Nanoporous crystalline structures can be achieved for a large variety of chemical compounds: inorganic (e.g., zeolites), 1 metal-organic, 2 as well as organic. 3 These materials, often referred as inorganic, metal-organic, and organic "frameworks", are relevant for molecular storage, recognition, and separation techniques.Recently, a "polymeric framework", i.e., a semicrystalline polymeric material presenting a nanoporous crystalline phase, has also been discovered. [4][5][6] In fact, the δ-phase of syndiotactic polystyrene (s-PS) presents two identical cavities and

Polymer co-crystalline films for photonics

“…This different type of nanoporosity generally leads, in co-crystals obtained from the ε phase, to an orientation of the guest molecular planes parallel to the polymer host chain-axes [5] rather than perpendicular, as generally observed [15,16] for co-crystals from the δ phase. Moreover the channel-shaped cavities of the ε-form allows to obtain co-crystals with guest molecules much longer than those hosted by the δ "polymeric framework" [5].…”

“…The channel-shaped cavities of the ε-form give the possibility to obtain co-crystalline phases with bulkier guests and molecules with a higher first order hyperpolarizability than trans-4-methoxy-β-nitrostyrene (β = 17 × 10 −30 esu) were found to form co-crystals [5].…”

“…Particularly efficient and versatile appears to be the encapsulation of chromophore molecules as guest of the host nanoporous crystalline phases (the so called δ [3,4] and ε [5,6] phases) of syndiotactic polystyrene (sPS). The δ nanoporous crystalline phase presents two identical cavities and eight styrene monomeric units per unit cell [3] (see Figure 1(a)) and is able to sorb volatile organic compounds (both from gas phase and aqueous solutions), also when present at very low concentrations [7]- [9].…”

Characterization of toluene and 2-methylnaphthalene transport separated by syndiotactic polystyrene having various crystalline forms

“…1-3 and b (orthorhombic, unit cell a ¼ 0.881 nm, b ¼ 2.828 nm, c ¼ 0.551 nm) 4,5 forms assume an all-trans sequence, whereas the g (uncertain monoclinic suggested, unit cell a ¼ 1. [13][14][15] forms assume a trans-trans-gauchegauche (ttgg) sequence. The all-trans conformation is thermally stabilized with a melting temperature as high as 270 1C.…”

Absorption Kinetics of Phenol into Different Size Nanopores Present in Syndiotactic Polystyrene and Poly (p-methylstyrene)

“…It has been reported that there are five crystalline modifications. The [4][5][6][7][8] and [9,10] forms consist of a planar zigzag chain with period of 5.1 Å, whereas the [11][12][13], [14][15][16][17], and [18][19][20] forms adopt a helical structure with a trans-trans-gauche-gauche (ttgg) conformation, having a period of 7.7 Å. The crystal with an all-trans conformation is a thermally stabilized form induced above about 180 °C and its high melting temperature around 270 °C is expected to be useful as an engineering plastic.…”