Rungswang W.,SCG Chemical Co. |
Jarumaneeroj C.,SCG Chemical Co. |
Petcharat N.,SCG Chemical Co. |
Soontaranon S.,Synchrotron Light Research Institute Public Organization Po Box 93 30000Nakhon Ratchasima Thailand |
Rugmai S.,Synchrotron Light Research Institute Public Organization Po Box 93 30000Nakhon Ratchasima Thailand
Journal of Applied Polymer Science | Year: 2017
Impact-resistance polypropylene copolymer (IPC) has been well known as commercial heterophasic polymer in which ethylene-propylene random copolymer (EPR) domain is dispersed in the homo-polypropylene (hPP) matrix. The phase-separation of those phases is one of the keys to control the polymer properties. However, especially in the solution, there is rarely report that addresses to the phase-separation of the IPC due to the difficulties in the investigation; i.e., (i) the proximity of the refractive indices of those phases and (ii) the small size of the EPR droplet. Here, the phase-separation of the commercial IPC in xylene is traced by the in situ small angle X-ray scattering (SAXS) which the phase-separation temperature is clearly revealed. The results also show that the evolution of the EPR domain is strongly depended on the polymer composition. Moreover, the migrations of the copolymers are evidenced, and this could be a model for other heterophasic systems. © 2017 Wiley Periodicals, Inc.
Luangon B.,Chulalongkorn University |
Siyasukh A.,Naresuan University |
Winayanuwattikun P.,Chulalongkorn University |
Tanthapanichakoon W.,SCG Chemical Co. |
Tonanon N.,Chulalongkorn University
Journal of Molecular Catalysis B: Enzymatic | Year: 2012
Hierarchical micro-/macroporous carbon monoliths are prepared as enzyme carriers for flow-through process. The immobilization of Candida rugosa lipase on micro-/macroporous carbon monoliths is studied. Lipase is immobilized by physical adsorption which lipase solution is circulated through the micro-/macroporous carbon monolith. An accessibility of lipase to the surface inside the micro-/macroporous carbon monolith is enhanced by flow-through method which promotes enzyme-surface interaction and finally leads to rapid enzyme immobilization. After immobilization is conducted for 10 min, the maximum protein binding can be measured. In terms of substrate-immobilized lipase reactions, flowing of substrate through lipase immobilized micro-/macroporous carbon monolith promotes high efficiency in both reaction and product withdrawal. Moreover, at high flow rates of lipase solution in immobilization step, the lipase activity increases. Oxygenated surface of micro-/macroporous carbon monoliths support also demonstrates an interesting effect on lipase immobilization and biocatalyst activity. The initial reaction rate of lipase immobilized on oxygenated surface carbon monolith support has higher activity compared with normal surface. © 2011 Elsevier B.V. All rights reserved.
Rungswang W.,SCG Chemical Co. |
Thongsak K.,SCG Performance Co. |
Prasansuklarb A.,SCG Plastics Co. |
Plailahan K.,Thai Polypropylene Co. |
And 3 more authors.
Industrial and Engineering Chemistry Research | Year: 2014
Although various types of nucleating agents (NA) have been used in polypropylene (PP) for commercial products, the effects of sodium salt and sorbitol based NAs on polymer structures and the relation to the physical properties have been rarely reported. The present work reveals structure and orientation of PP crystal with direct comparison of two types of NAs, i.e., sodium salt and sorbitol-derivative, via X-ray scattering techniques. The results show how those crystal structures are related to the properties of injected-mold PP, with the emphasis on the compressive strength and shrinkage. © 2014 American Chemical Society.