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Reactive blending of aromatic polyesters: Thermal and X‐ray analysis of melt‐blended poly(ethylene terephthalate)/poly(trimethylene terephthalate)

“…31,32,34 If the blends are kept in the melt for a prolonged period of time, some transesterification, evidenced by modification of the melting behavior, takes place. 11,33 New signals have not been observed in the WAXD patterns; only overlapping of the crystalline peaks of the two polyesters has been found, and this suggests the formation of block copolymers. 33,34 In a certain composition range, fibers with outstanding properties can be achieved from blends of PTT and PET.…”

“…6 Like PET, 7 PTT crystallizes in a triclinic crystal structure, with the periodicity along the c axis containing two repeating units and the methylene groups being arranged in a highly contracted gauche-gauche con-formation. 2,8,9 Several articles have appeared recently in the literature concerning the physical properties of PTT, [10][11][12][13][14][15] such as its outstanding resilience, ability to rapidly crystallize, morphological structure, and fiber properties.…”

“…[27][28][29][30] Some articles concerning blends of PET and PTT have also been published in recent years. 11,[31][32][33][34][35][36][37][38] Evidence for miscibility restricted to amorphous regions is provided in all these articles, and the crystallization behavior and wide-angle X-ray diffraction (WAXD) patterns suggest that the pure PET and PTT components crystallize simultaneously to form their own crystalline entities; this means that the unit cells remain individually different even if they coexist in the same bundles or spherulites. 31,32,34 If the blends are kept in the melt for a prolonged period of time, some transesterification, evidenced by modification of the melting behavior, takes place.…”

Synthesis and absorbency of a superabsorbent from sodium starch sulfate-g-polyacrylonitrile

“…Research on superabsorbents was initiated by the development of a starch-based superabsorbent, Superslurper, by the U.S. Department of Agriculture, Northern Regional Research Center, in the late 1960s. 1 Since then, modification of natural raw materials such as starch, 2 cellulose, 3,4 and protein 5 and direct synthesis from hydrophilic monomers such as acrylamide 6,7 and acrylic acid 8,9 with crosslinkers have been utilized to prepare superabsorbents.…”

Relationship between colour fastness and colour strength of polypropylene fabrics dyed in supercritical carbon dioxide: effect of chemical structure in 1,4‐bis(alkylamino)anthraquinone dyestuffs on dyeing performance

“…They then evaluated dyeing properties (dye uptake, fastness), as well as undertaking optical microscopical analyses, X-ray birefringence analyses, mechanical tests and differential scanning calorimetry (DSC) analyses [41,42]. Dyeing of polypropylene in an aqueous system with a special dispersing agent has also been studied [43][44][45][46][47][48][49]. It was found that the dyestuffs for polypropylene fibres need to be much more hydrophobic than common disperse dyes for poly(ethylene terephthalate) fibre.…”