Prepolimeri tal-Poliuretejn ibbażati fuq l-Ester Kwasi-MDI Għall-Elastomer Cast

In principle, a prepolymer could be formed by reacting diisocyanates with an excess of polyol to produce a polyol functional prepolymer with urethane functionality at its center, but this is not practiced commercially and the term "prepolymer" is always used to refer to polyols terminated with isocyanate functionality. The excess isocyanate is required to prevent molecular weight growth caused by opportunistic chain extension of unreacted polyol reacting with the isocyanate-terminated prepolymer. In practice, chain extension always occurs but can be limited by increasing the ratio of isocyanate to hydroxyl functionality. A true "prepolymer" in this regard would then distill the excess isocyanate from the product. In the case where the excess isocyanate is left in the product, this is referred to as a "quasi-prepolymer". In practice, quasi-prepolymer refers to systems with relatively high levels of free isocyanate (>12%), filwaqt li prepolimeru jirreferi għal sistemi b'livelli baxxi ta' isocyanates ħielsa (<12%). Overall, over 400 million pounds a year of prepolymer is used commercially for many applications where the advantages of prepolymers can be realized.

Dan il-prepolimeri tal-Polyurethane bbażati fuq l-ester Kwasi-MDI jikkonsisti fi tliet komponenti A/B/C. Komponent A huwa prepolimeru tal-poliester Kwasi-MDI li spiċċa b'isoċinat, Komponent B huwa polyol tal-poliester, Komponent C huwa 1,4BDO.

Is-sistemi kważi prepolimeri tagħha jistgħu jipprovdu ċerti vantaġġi fuq il-prepolimeri sħaħ aktar konvenzjonali billi joffru prepolimeri u kurattivi ta 'viskożità aktar baxxa, temperatura tal-materjal aktar baxxa għall-ipproċessar, elastomeri b'ħafna ebusija bl-istess sistema, kif ukoll kura ambjentali u tas-saħħa aħjar.

Il-vantaġġ ewlieni jinsab fi żmien qasir ta 'demoulding, li jippermetti żieda fil-produttività.

• Proprjetajiet mekkaniċi eċċellenti
• Reattività aġġustabbli, jiġifieri l-għażla tal-katalizzatur u l-proporzjon tat-taħlita
• Adattat għall-ikkastjar ta 'partijiet kbar ħafna
• Alternattivi vijabbli għal sistemi li jistgħu jiffaċċjaw restrizzjonijiet regolatorji
• Tnaqqis fil-konsum tal-enerġija għal aktar sostenibbiltà

Sistemi bbażati fuq l-ester kważi-MDI joffru reżistenza superjuri għall-brix u d-dmugħ b'reżistenza eċċellenti għal kimiċi bħal idrokarburi, żjut u solventi. Dawn is-sistemi huma għażla ideali għal applikazzjonijiet bħal skrins, scrapers, PIGs, xfafar tal-konkrit, folji u skutelli vibratorji.

Din is-Sistema Kwasi MDI POLYESTER Normalment ippakkjata f'tanbur tal-ħadid ta '200kg/

It-tags Popolari: prepolimeri tal-polyurethane kważi mdi bbażati fuq ester għal elastomer fondut, Ċina prepolimeri tal-polyurethane bbażati fuq ester kważi mdi għal manifatturi ta 'elastomer fondut, fornituri, fabbrika