• Korean Journal of Environment and Ecology
• /
• v.28 no.3
• /
• pp.357-364
• /
• 2014

This study aimed to determine effects of the use of water-retention additive, hydrophilic polymer, for extensive green roofs on growth of Juniperus chinensis var. sargentii and Euonymus fortunei 'Emerald and Gold' for woody plants, and Carex kobomugi and Carex pumila for herbaceous plants. Five different contents of hydrophilic polymer including 0% (Control), 1.0%, 2.5%, 5.0%, and 10% (polymer: medium (w/w), dry weight basis) were added to each of the container filed with a 100 kg of growth medium. Ten of plants were transplanted in each of square container ($1m(L){\times}1m(W){\times}0.3m$ (H)) built on the roof platforms in randomized complete block design in the $20^{th}$ of May, 2013. In results, excessively high volumetric soil water content, about 97-98%, was found in the substrate under elevated hydrophilic polymer concentration of at least 2.5%, during the entire growing period. The moisture content of the substrate containing 1.0% of hydrophilic polymer was higher about 20% in the range between 70% and 80%, compared tho that of Control substrate in the range between 50% and 60%, for 27 days after transplanting prior to abundant rainfall, indicating that the application of hydrophilic polymer to the extensive green roof substrate is effective to eliminate drought condition by retaining water in the substrate. Euonymus fortunei 'Emerald and Gold' and Carex kobomugi resulting in higher plant growth with 2.5% than those of the other treatment plants. Juniperus chinensis var. sargentii was observed the highest growth under 1.0% hydrophilic polymer treatement, and Carex pumila was founded the best growth with Control respectively. Plants that grown in both the 1.0% and 2.5% hydrophilic polymer survived all, while the plants that grown in the 5.0% and 10% hydrophilic polymer died after 3 months. These results suggest that advantage of the addition of hydrophilic polymer may be greater in drought-tolerant plants, but the mixture proportion of hydrophilic polymer should be determined according to the different features of the plant species being grown.

• Macromolecular Research
• /
• v.9 no.1
• /
• pp.51-65
• /
• 2001

Two-stage emulsion polymerizations of hydrophobic monomers on hydrophilic seed polymer particles were carried out to make core-shell composite particles. It was found that the loci of polymerization in the second stage were the surface layer of the hydrophilic seed latex particles, and that it has resulted in the formation of either eccentric core-shell particles with the core exposed to the aqueous phase or aggregated nonspherical composite particles with the shell attached on the seed surface as many small separated particles. The driving force of these phenomena is related to the gain in free energy of the system in going from the hydrophobic polymer-water interface to hydrophilic polymer-water interface. Thermodynamic analysis of the present polymerization system, which was based on spreading coefficients, supported the likely occurrence of such nonspherical particles due to the combined effects of interfacial free energies and phase separation between the two polymer phases. A hypothetical pathway was proposed to prepare hydrophilic core-hydrophobic shell composite latex particles, which is based on the concept of opposing driving and resistance forces for the phase migration. It was found that the viscosity of the monomer-swollen polymer phase played important role in the formation of particle morphology.

• Journal of Environmental Science International
• /
• v.21 no.12
• /
• pp.1469-1476
• /
• 2012

Hydrophilic polymer is suitable as soil conditioners for green roofs that use rainwater, due to promotion of water retention capacity as well as enhancement of the water absorbing capacity. The objective of the present study was to investigate the effects of different levels of hydrophilic polymer concentrations (0, 0.1, 0.2, 0.4, 0.8% w/w) on the water holding capacity and growth response of 6 species in soils amended with hydrophilic polymer in 5 cm of soil thickness on green roofs. The results showed that the water holding capacity of the amended soil improved with increasing amount of applied polymer. The application of 0.8% w/w of the polymer increased the soil moisture by 87% compared to the control, and decreased slowly in green roofs during an arid period. The growth of Sedum spurium 'Dragon's blood' and Lampranthus spectabilis increased significantly and had greater than 60% relative coverage with higher hydrophilic polymer concentrations. However, Juniperus chinensis var. sargentii and Euonymus fortunei var. radicans had no significant differences upon change of hydrophilic polymer concentrations. In Carex kujuzana and Carex morrowii 'Aurea variegata', growth decreased with increase of hydrophilic polymer concentrations. 30 days after planting, Juniperus chinensis var. sargentii, Euonymus fortunei var. radicans, Carex kujuzana, and Carex morrowii 'Aurea variegata' died back due to lowest soil thickness (5 cm), but Sedum spurium 'Dragon's blood' and Lampranthus spectabilis had greater than 90% survival.

• Journal of Environmental Science International
• /
• v.25 no.5
• /
• pp.625-633
• /
• 2016

This study was conducted to investigate the influence of hydrophilic polymer (HP) mixture ratio (Control, 1.0%, 2.5%, 5.0%, and 10.0%) on growth of eggplant (Solanum melongena) for lower maintenance urban agriculture via green roofs. Although it was not statistically significant (p > 0.05), substrate temperature was decreased as hydrophilic polymer mixture ratio were increased. High substrate water content (95%) was found consistently in growing media under elevated hydrophilic polymer mixture ratio at over 5% during the entire growing period. Substrate electronic conductivity was increased as hydrophilic polymer mixture ratio were increased. Growth index was decreased as hydrophilic polymer mixture ratio was increased. It was reduced about 1/3 and 1/5 compared to that of Control in HP5.0 and HP10.0 treatment plants, respectively. Number of leaves, leaf length, and leaf width were decreased in following order: Control> HP1.0> HP2.5> HP5.0> HP10.0 treatments. There numbers were significantly lower in HP5.0 and HP10.0 treatment plants. Dry weight of shoot and root were decreased as hydrophilic polymer mixture ratio was increased. They were reduced by 1/4 compared to those of Control treatment plants. In addition, visual value was decreased as hydrophilic polymer mixture ratio was increased. Plants grown in HP1.0, HP2.5, and HP5.0 treatments all survived. However, plants grown in the HP10.0 treatment had the lowest survival rate (56%) after 3 months of growing. These results indicate that the advantage of adding hydrophilic polymer to green roof growing media may greater during dry periods. However, the proper mixture proportion of hydrophilic polymer should be determined according to different characteristics of growing media and plant species.

• Korean Chemical Engineering Research
• /
• v.56 no.3
• /
• pp.370-375
• /
• 2018

In this study, we have applied fractional precipitation with hydrophilic polymer in order to decrease the particle size of the (+)-dihydromyricetin from plant materials. When compared with the case where no hydrophilic polymer was employed, the addition of hydrophilic polymer in fractional precipitation resulted in a considerable decrease in the size of the (+)-dihydromyricetin precipitate. Among the polymers used, HPMC 2910 was the most effective for inhibition of precipitate growth. A polymer concentration of 0.1% (w/v) yielded the smallest particle size. The particle size was reduced by ~40% compared to control. In addition, the precipitate size was inversely correlated with the absolute value of the zeta potential of the suspension with polymer.

• Journal of the Korean Vacuum Society
• /
• v.8 no.3B
• /
• pp.262-268
• /
• 1999

Polycarbonate (PC) and Polymethylmethacrylate (PMMA) surface was modified by ion assisted reaction (IAR) technique to obtain the hydrophilic functional groups and improve the wettability. In conditions of ion assisted reaction, ion beam energy was changed from 500 to 1500eV, and ion dose and oxygen gas blown rate were fixed $1\times10^{16}$ ions/$\textrm{cm}^2$ and 4ml/min, respectively. Wetting angle of water on PC and PMMA surface modified by $Ar^+$ ion without blowing oxygen at 4ml/mon showed $5^{\circ}$ and $10^{\circ}$. Changes of wetting angle with oxygen gas and $Ar^+$ ion irradiation were explained by considering formation of hydrophilic group due to a reaction between irradiated polymer chain by energetic ion irradiation and blown oxygen gas. X-ray photoelectron spectroscopy analysis shows that hydrophilic groups such as -C-O, -(C=O)- and -(C=O)-O- are formed on the surface of polymer by chemical interaction. The polymer surface modification using ion assisted reaction only changed the surface physical properties and sept the bulk properties. In comparison with other modification methods, the surface modification by IAR treatment was chemically stable and enhanced the adhesion between metal and polymer surface. The applications of various kinds of polymer surface modification methods, metal and polymer surface. The applications of various kinds of polymer surface modification could be appled to the new materials about hydrophilic surface properties by IAR treatment. The adhesion between metal film and polymer measured by Scotch tape test whether the hydrophilic surfaces could improve the adhesion strength or not.

• Macromolecular Research
• /
• v.11 no.2
• /
• pp.115-121
• /
• 2003

In this research, the in vitro anti-thrombogenecity of artificial materials was evaluated using hydrophilic/hydrophobic copolymers containing oiligosaccharide as hydrophilic moiety and phospholipid as hydrophobic moiety respectively. N-(p-vinylbenzyl)-[O-$\alpha$-D-glucopyranosyl-(1longrightarrow4)]$_{n-1}$-D-glucoamide(VM7A) was (VM7 A) was adopted as hydrophilic oligosaccharide and 2-acryloxybutyl-2-(triethylammonium)ethyl phosphoric acid (HBA-choline) was adopted as hydrophobic phospholipid. Copolymers having various monomer feeding molar ratios were synthesized through radical polymerization. The synthesized copolymers were identified using FT-IR, $^1$H-NMR, XPS, and DSC. The surface energy of the copolymers were evaluated by dynamic contact angle (DCA) method and checked different roles of VM7A as hydrophilic moiety and HBA-choline as hydrophobic moiety on surface. The surface morphological differences between hydrated and unhydrated surfaces of copolymers were observed and evaluated using Am. The platelets were separated from canine whole blood by centrifugation and adopted to the anti-thromobogenecity test of the copolymers. From the results, we find out that as VM7A ratio increases, so did anti-thrombogenecity. Such results show the possibility of using these copolymers as blood compatible materials in living body.y.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.229-229
• /
• 2007

In this study, HEMA-based hydrophilic copolymers were synthesized and dielectric constant (K) of the polymer thin films were investigated by change hydroxyl group (-OH) ratio in the polymer chain. The different hydroxyl group ratios were characterized by FT-IR and its thin films were obtained by spin coating. As a result, due to the moisture absorption of the hydrophilic thin film, the dielectric constant has been increased as was expected. The highest dielectric constant (K=4.19, @1MHz) was observed at 40% hydroxyl group ratio among the several polymers.

• YAKHAK HOEJI
• /
• v.31 no.1
• /
• pp.25-32
• /
• 1987

The effect of loading dose, plasticiser and PVA molecular weight on naproxen release from hydrophilic polymer matrix was examined. Hydrophilic polymer matrix was prepared with PVA and PVP by adding glycerine as plasticiser. The release of naproxen from polymer matrix was determined in phosphate buffer medium. The release rate of naproxen from the polymer matrix increased as drug loading dose and plasticiser percentage increased. Raproxen released from the polymer matrix showed the time square root kinetics. Without changing the release-pattern, the release rate of naproxen could not be changed by varying molecular weight of PVA. Linearly released time range increased as drug loading dose increased, whereas decreased as plasticiser percentage increased up to 30%.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1999.07a
• /
• pp.161-161
• /
• 1999

In the field of material science, the interests and efforts to modify the surface of materials in agreement with the need of usage have been extensively increasing. he modification to improve the wettability of surface is very important is terms of adhesion, printing, etc. It is very difficult to modify metal surface into hydrophilic one. therefore, surfactant coating has been generally used in many cases. However, surfactant has disadvantages such as environmental problem, soluble in water. in this study, hydrophilic polymer films as alternative of surfactant were deposited on metal substrate by DC plasma polymerization. Hydrophilic polymer films deposited by DC plasma show many merits such as good wettability, stone adhesion to substrate, high resistance to most chemicals. Monomer gas and reactive gas were used as source plasma polymerization. Plasma polymerized films were fabricated with process parameters of deposition time, ratio of gas mixture, current, pressure, etc. Effects of these variables on wettability of plasma polymer films will be discussed. With XPS and FT-IR analyses of plasma polymeric films, the relation between wettability and chemical state of polymer films by DC plasma was investigated.