東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Clay-tethered thermoplastic polyuret...

Pattanayak, Asim.

Linked to FindBook

Google Book

Amazon

博客來

Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods./
Author:	Pattanayak, Asim.
Description:	180 p.
Notes:	Source: Dissertation Abstracts International, Volume: 66-05, Section: B, page: 2772.
Contained By:	Dissertation Abstracts International66-05B.
Subject:	Engineering, Materials Science. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3175337
ISBN:	9780542137334

Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods.
Pattanayak, Asim.

Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods. - 180 p.

Source: Dissertation Abstracts International, Volume: 66-05, Section: B, page: 2772.

Thesis (Ph.D.)--The University of Akron, 2005.

In this study, thermoplastic polyurethane nanocomposites of reactive silicate clays were synthesized by bulk polymerization methods and their thermal, rheological, and mechanical properties were evaluated and compared with those of non-reactive clays. The --OH groups contained in quaternary ammonium ions were used for clay-polymer tethering. Two methods were used for synthesis of nanocomposites. In Method I, the clay particles were allowed to react with prepolymer, followed by chain extension by butanediol with residual --NCO groups. In Method II, chain extended polyurethane polymer was mixed with organoclay particles. It was found that both clay-polymer reactions and shear stress of mixing are necessary for clay exfoliation. It was also found that hydrogen bonding did not contribute to clay exfoliation and to final mechanical properties. We found that nanocomposites were produced only in the case of reactive clays with Method II, which provided 110% increase in tensile modulus, 170% increase in tensile strength, 110% increase in tear strength, 120% increase in fracture toughness, and about 40% increase in abrasion resistance with 5wt% clay content. A separate study on kinetics of clay-polymer reactions revealed that these reactions are much slower than urethane reactions and therefore, longer times must be provided to generate enough clay-polymer tethering.

ISBN: 9780542137334Subjects--Topical Terms:

1017759
Engineering, Materials Science.

Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods.
LDR:02678nmm 2200301 4500 001 1823923
005 20061128084426.5
008 130610s2005 eng d
020 $a 9780542137334
035 $a (UnM)AAI3175337
035 $a AAI3175337
040 $a UnM $c UnM
100 1 $a Pattanayak, Asim. $3 1913017
245 1 0 $a Clay-tethered thermoplastic polyurethane nanocomposites by bulk polymerization methods.
300 $a 180 p.
500 $a Source: Dissertation Abstracts International, Volume: 66-05, Section: B, page: 2772.
500 $a Adviser: Sadhan C. Jana.
502 $a Thesis (Ph.D.)--The University of Akron, 2005.
520 $a In this study, thermoplastic polyurethane nanocomposites of reactive silicate clays were synthesized by bulk polymerization methods and their thermal, rheological, and mechanical properties were evaluated and compared with those of non-reactive clays. The --OH groups contained in quaternary ammonium ions were used for clay-polymer tethering. Two methods were used for synthesis of nanocomposites. In Method I, the clay particles were allowed to react with prepolymer, followed by chain extension by butanediol with residual --NCO groups. In Method II, chain extended polyurethane polymer was mixed with organoclay particles. It was found that both clay-polymer reactions and shear stress of mixing are necessary for clay exfoliation. It was also found that hydrogen bonding did not contribute to clay exfoliation and to final mechanical properties. We found that nanocomposites were produced only in the case of reactive clays with Method II, which provided 110% increase in tensile modulus, 170% increase in tensile strength, 110% increase in tear strength, 120% increase in fracture toughness, and about 40% increase in abrasion resistance with 5wt% clay content. A separate study on kinetics of clay-polymer reactions revealed that these reactions are much slower than urethane reactions and therefore, longer times must be provided to generate enough clay-polymer tethering.
520 $a Composites prepared by Method I, with --NCO to --OH molar ratio of 1.0 failed to produce good nanocomposites due to appreciable reactions of --NCO groups with moisture present in clay. It was found that with excess --NCO, e.g., with --NCO : --OH ratio of 1.1, 60% increase in tensile strength and 50% increase in strain at break with 5 wt% clay can be obtained.
590 $a School code: 0003.
650 4 $a Engineering, Materials Science. $3 1017759
650 4 $a Plastics Technology. $3 1023683
650 4 $a Chemistry, Polymer. $3 1018428
690 $a 0794
690 $a 0795
690 $a 0495
710 2 0 $a The University of Akron. $3 1018399
773 0 $t Dissertation Abstracts International $g 66-05B.
790 1 0 $a Jana, Sadhan C., $e advisor
790 $a 0003
791 $a Ph.D.
792 $a 2005
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3175337