04009ntm a2200325 i 4500003000800000005001700008006001900025008004100044020003200085040002300117100003000140245010700170264003400277264001200311300007100323336002100394336002100415337002500436337002300461338002300484338003000507347002400537500005900561502007000620504004000690520282300730610007403553650004503627650001103672MY-KuUP20251125110000.0t||||fr|||| 000 0 220316s2021    my a|||frm||| 00| 0 eng d  aTHE0009169(Local)qhardback  aUMPbengcUMPerda1 aNajahusna Adnan,eauthor.10aSynthesis and characterization of superporous hydrogels by using gas blowing method /cNajahusna Adnan 1aKuantan, Pahang :bUMP,c2021 4c© 2021  axiii, 69 pages :billustrations (some color) ;c30 cm. +e1 CD-ROM  atext2rdacontent  atext2rdacontent  aunmediated2rdamedia  acomputer2rdamedia  avolume2rdacarrier  acomputer disc2rdacarrier  atext filebPDF2rda  aFaculty of Chemical and Process Engineering Technology  aThesis (Master of Science) -- Universiti Malaysia Pahang – 2021  aIncludes bibliographical references3 aSuperporous hydrogels (SPHs) is a three-dimensional network of a hydrophilic polymer  that  absorbs  a  large  amount  of  water  in  a  very  short  period  due  to  the  presence  of interconnected  microscopic pores.  The invention of superporous hydrogels is made up  for modification of superabsorbent polymers (SAPs) due to the slow swelling properties.  The present SAP contains less porous structure, thus produced slow swelling properties  of the SAPs. The swelling rate of most SAPs is typically low and takes a longer time to  reach equilibrium due to the slow water absorption capability. This disadvantage further  limits the possible application of the hydrogel to be utilized in various fields, including  as  drug  delivery  material  and  as  soil  conditioner  in  agriculture.  Therefore,  there  is  a  significant  interest  in  developing  synthesis  methods  and  the  selection  of  material  in  preparation of the SPH  that can produce fast swelling absorption properties. In this study,  SPHs were prepared from monomer of acrylamide (AM) and co-monomer acrylic acid  (AA) by using gas blowing method with ammonium persulphate (APS) as an initiator  and  N’N’-methylenebisacrylamide  (MBA)  as  cross  linker.  The  effects  of  sodium  bicarbonate (NaHCO3) concentration (0 wt%  -  5 wt%) as foaming agent, acetic acid (0  wt%  -  5 wt%) as foaming aid and Span 80 (0 wt%  -  7.5 wt%) as foam  stabilizer were  studied by determined the water absorbency, morphology (SEM), compression strength,  functional group (FTIR), thermal stability (TGA) and swelling kinetics of SPHs. Based  on the optimum results, it shows that effect of foaming agent (NaHCO3)  optimum at 4  wt% (178g/g) while effect of foaming aid optimum at 0 wt% as the addition of acetic acid  has no significant difference with 0 wt%. then, the effect of foaming stabilizer (Span 80)  optimize at 4.5 wt% where it gives the highest water absorbency at 206 g/g. The factor  that contributed to the high water absorbency is mainly due to the formation of various  sizes  of  pores  in  the  structures  of  SPHs  which  allow  the  penetration  of  water  which  characterized by SEM. Based on the morphology results, the  final 4.5 wt% Span 80 SPHs  produce higher water absorbency due to present of many pore with uniform size in the  SPHs structures. Then, the swelling rate also supports the foaming stabilizers effect as  the  4.5  wt%  Span  80  gives  the  higher  water  absorbency  at  shorter  time.  Lastly,  the  swelling kinetics results show that the SPHs obeyed the second order with diffusivity  value, n  is less than 0.5 as indicates that it follows the Fick’s Law. As a conclusion, SPHs  prepared  by  gas  blowing  technique  gave  better  performance  of  pore  formation  on  superporous hydrogels.20aFaculty of Chemical and Process Engineering TechnologyxDissertations 0aUniversities and collegesxDissertations 0aTheses