Polyurethane AB Adhesive Powder Flame Retardant Formulations

Polyurethane AB Adhesive Powder Flame Retardant Formulations
Zvichienderana nezvinodiwa zvehalogen-isina flame retardant formulations ye polyurethane AB adhesives, yakasanganiswa nehunhu uye synergistic mhedzisiro yemurazvo retardants sealuminium hypophosphite (AHP), aluminium hydroxide (ATH), zinc borate, uye melamine cyanurate (MCA), matatu anotevera ekubatanidza zvirongwa akagadzirwa. Aya magadzirirwo haana chlorine-isina uye anotarisa pakugadzirisa murazvo unodzora kushanda zvakanaka, kuenderana kwekuita kwemuviri, uye kugona kwekuita:

1. High Flame Retardancy Formulation (Zvemagetsi potting, bhatiri encapsulation, chinangwa UL94 V-0)

Core Flame Retardant Combination:

• Aluminium hypophosphite (AHP): 8-12 phr (waterborne polyurethane-coated type inokurudzirwa kugadzirisa nyaya dzekunaya)
• Aluminium hydroxide (ATH): 20-25 phr (submicron giredhi, 0.2-1.0 μm, kuwedzera oksijeni index uye char compactness)
• MCA: 5-8 phr (gas-phase mechanism, synergistic neAHP muchikamu chakapfupikiswa)
• Zinc borate: 3-5 phr (inokurudzira ceramic char kuumbwa uye inhibits kuputa)

Zvinotarisirwa Kuita:

• Oxygen index (LOI): ≥32% (pure PU ≈22%);
• UL94 chiyero: V-0 (1.6 mm ukobvu);
• Thermal conductivity: 0.45-0.55 W/m·K (yakapiwa neATH uye zinc borate);
• Viscosity control: 25,000-30,000 cP (kurapwa kwepamusoro kunodiwa kudzivirira sedimentation).

Key process:

• AHP inofanira kunge isati yaparadzirwa muchikamu che polyol (Chikamu A) kudzivirira kuita nguva isati yakwana ne isocyanate (Chikamu B);
• ATH inofanirwa kugadziridzwa ine silane coupling agent (semuenzaniso, KH-550) kuti iwedzere kubatana kwemeso.

2. Yakaderera-Mutengo General Magadzirirwo (Pakuvaka chisimbiso, fenicha bonding, chinangwa UL94 V-1)

Core Flame Retardant Combination:

• Aluminium hydroxide (ATH): 30-40 phr (yakajairika micron-giredhi, inodhura-inoshanda, filler-mhando murazvo retardant);
• Ammonium polyphosphate (APP): 10-15 phr (yakasanganiswa neMCA kune intumescent system, kutsiva halogenated agents);
• MCA: 5-7 phr (chiyero kune APP 1: 2 ~ 1: 3, inokurudzira kupupa uye kuparadzaniswa kweokisijeni);
• Zinc borate: 5 phr (kuderedza utsi, kuumbwa kwechar).

Zvinotarisirwa Kuita:

• LOI: ≥28%;
• UL94 chiyero: V-1;
• Kuderedza mari: ~ 30% (ichienzaniswa nepamusoro-moto-retardancy formulation);
• Kuchengetedza simba rekusimba: ≥80% (APP inoda encapsulation kudzivirira hydrolysis).

Key process:

• APP inofanirwa kuve microencapsulated (semuenzaniso, ine melamine-formaldehyde resin) kudzivirira kunyura hunyoro uye kuumbwa kwebubble;
• Wedzera 1-2 phr hydrophobic fumed silica (semuenzaniso, Aerosil R202) yekurwisa-kugadzirisa.

3. Low-Viscosity Easy-Process Formulation (Nokuda kwechokwadi chemagetsi bonding, chinoda kuyerera kwakanyanya)

Core Flame Retardant Combination:

• Aluminium hypophosphite (AHP): 5-8 phr (nanosized, D50 ≤1 μm);
• Liquid organic phosphorus flame retardant (BDP imwe nzira): 8-10 phr (semuenzaniso, halogen-isina phosphorus-based DMMP derivatives, kuchengetedza viscosity);
• Aluminium hydroxide (ATH): 15 phr (spherical alumina composite, kuenzanisa thermal conductivity);
• MCA: 3-5 phr.

Zvinotarisirwa Kuita:

• Viscosity range: 10,000-15,000 cP (padhuze nemagetsi emoto retardant systems);
• Flame retardancy: UL94 V-0 (yakasimudzirwa nemvura phosphorus);
• Thermal conductivity: ≥0.6 W/m·K (yakapihwa ne spherical alumina).

Key process:

• AHP uye spherical alumina inofanira kunge yakasanganiswa uye yakaparadzirwa pasi pepamusoro shear (≥2000 rpm);
• Wedzera 4-6 phr molecular sieve desiccant kuChikamu B kudzivirira AHP kunwa hunyoro.

4. Kubatanidza Technical Points & Alternative Solutions

1. Synergistic Mechanisms:

• AHP + MCA:AHP inosimudzira kupera mvura mumuviri uye kupisa, ukuwo MCA inoburitsa nitrogen gasi pakudziya, ichigadzira muzinga-senge char layer.
• ATH + zinc borate:ATH inobata kupisa (1967 J/g), uye zinc borate inoumba borate girazi layer kuvhara pamusoro.

2. Alternative Flame Retardants:

• Polyphosphazene derivatives:High-inoshanda uye eco-hushamwari, ine byproduct HCl kushandiswa;
• Epoxy silicone resin (ESR):Kana yasanganiswa neAHP, inoderedza kurodha kwese (18% yeV-0) uye inovandudza ma mechanic properties.

3. Kudzora Njodzi:

• Sedimentation:Anti-settling agents (semuenzaniso, polyurea-modified types) inodiwa kana viscosity <10,000 cP;
• Kurapa inhibition:Dzivisa akawandisa alkaline murazvo retardants (semuenzaniso, MCA) kudzivirira kukanganiswa neisocyanate maitiro.

5. Implementation Recommendations

• Isa pamberi kuyedza iyo yakakwirira-murazvo-retardancy kuumbwa: yakavharwa AHP + submicron ATH (avhareji saizi 0.5 μm) paAHP: ATH: MCA = 10:20:5 yekutanga optimization.
• Miedzo yakakosha:
  → LOI (GB/T 2406.2) uye UL94 vertical kutsva;
  → Bond simba mushure mekupisa bhasikoro (-30 ℃ ~ 100 ℃, 200 maawa);
  → Kunaya kwemoto kudzoreredza kunaya mushure mekukurumidza kuchembera (60 ℃/7d).

Flame Retardant Formulation Table