Forum Sains Indonesia




*

Artikel Sains

Aku Cinta ForSa

ForSa on FB  ForSa on Twitter

Pranala Luar

ShoutBox!

Last 10 Shouts:

dhea252

Agustus 19, 2016, 11:20:05 AM
Very good idea you've shared here, from here I can be a very valuable new experience. all things that are here will I make the source of reference, thank you friends.
http://obatambeien.tasikstore.com/
http://obatambeien.healthylifeindonesia.com/
http://obatambeien.bestagaric.web.id/
http://obat

dhea252

Agustus 19, 2016, 11:19:44 AM
Thanks for sharing, success always
http://obatambeien.tasikstore.com/

kez0223

Agustus 18, 2016, 09:14:36 AM
Thanks for sharing, success always

http://obatkolesterol.healthylifeindonesia.com/

kez0223

Agustus 18, 2016, 09:14:11 AM

kez0223

Agustus 18, 2016, 09:13:27 AM
The information is so exciting, very enjoyable to be listened

http://obatkolesterol.best-agaric.net/
http://obatkolesterol.best-agaric.com/

kez0223

Agustus 18, 2016, 09:12:56 AM
It is interesting to read, I hope the future is much better


http://obatkolesterol.agaricpro.info/
http://obatkolesterol.agaricpro.net/

kez0223

Agustus 18, 2016, 09:12:19 AM
Wow, I like the way you design this web... It's so beautiful.

http://obatkolesterol.agaricpro.biz/
http://obatkolesterol.agaricpro.org/

kez0223

Agustus 18, 2016, 09:11:35 AM

auzyouchen

Agustus 03, 2016, 09:53:07 AM
selamat pagi
Kutip

agaricback

Juli 29, 2016, 08:43:47 AM
ada hukum archimedes yang dimana masanya berkurang karena adanya udara..
http://goo.gl/aXAJAC | http://goo.gl/4nts9p | http://goo.gl/SqrQc0 | http://goo.gl/H4YOdC |

Show 50 latest

Penulis Topik: Vitamin C dan plastik  (Dibaca 4139 kali)

0 Anggota dan 1 Pengunjung sedang melihat topik ini.

Offline reborn

  • Founder
  • Profesor
  • *****
  • Tulisan: 2238
  • IQ: 317
  • Gender: Pria
  • ForSa
    • Lihat Profil
Vitamin C dan plastik
« pada: Maret 04, 2007, 05:03:35 PM »
http://www.nsf.gov/news/news_summ.jsp?cntn_id=108123&org=NSF&from=news

Vitamin C and Water : Healthy for Plastics

Two new laboratory breakthroughs are poised to dramatically improve how plastics are made by assembling molecular chains more quickly and with less waste. Using such environmentally friendly substances as vitamin C or pure water, the two approaches present attractive alternatives to the common plastic manufacturing technique called free radical polymerization (FRP).

"The methods both present novel and complementary ways to dramatically improve efficiency, product control, and cost for the polymer industry," said Andy Lovinger, the National Science Foundation program director who oversees funds for the two projects. "Each of these approaches could have a very significant impact on polymer manufacturing."

Plastics are polymers, long, potentially complex, molecule chains crafted from an array of smaller chemical units.  Using FRP, chemical engineers can create the right plastic for a range of applications, such as a specific trim for a car door or soft foam for a pillow.

For some plastics, the building-block molecules do not easily link together.  To surmount this problem, researchers from Carnegie Mellon University in Pittsburgh, Pa., devised a process called atom transfer radical polymerization (ATRP), which provides creative ways to coax the chemical subunits into chains.  However, this method comes with certain costs, such as the need for a copper catalyst that can become unwanted waste.

Now, the Carnegie Mellon researchers have discovered that adding vitamin C, glucose, or other electron-absorbing agents to the ATRP process can reduce the amount of copper catalyst by a factor of 1000. Because the catalyst often needs to be removed from the end products, less copper means far less waste and drastically reduced removal costs. Mass manufacturing could become more affordable for a range of items such as advanced sensors, drug delivery systems, paint coatings, and video displays.

At the University of Pennsylvania (UPenn), researchers are using a different approach to improve FRP. Called single electron transfer-living radical polymerization, the new method relies upon relatively low-energy reactions, uses elemental copper (copper metal, as opposed to copper in a chemical solution) as a catalyst to limit byproducts and allows manufacturers to use one of the most environmentally friendly solvents in the arsenal, water.  The entirely new method of polymerization builds upon existing mechanisms to craft large molecules very quickly.



 

Topik Terkait

  Subyek / Dimulai oleh Jawaban Tulisan terakhir
3 Jawaban
7003 Dilihat
Tulisan terakhir Mei 22, 2009, 08:17:08 AM
oleh syx
2 Jawaban
7645 Dilihat
Tulisan terakhir November 23, 2009, 06:13:00 AM
oleh Mat Dillom
0 Jawaban
7444 Dilihat
Tulisan terakhir Juli 27, 2010, 04:33:45 PM
oleh windhu17
9 Jawaban
4379 Dilihat
Tulisan terakhir Agustus 31, 2010, 04:51:44 PM
oleh syx
9 Jawaban
4259 Dilihat
Tulisan terakhir Juni 07, 2015, 08:20:51 AM
oleh MuhammadRyan

Copyright © 2006-2014 Forum Sains Indonesia