N-iso-Propylacrylamide

• CAS: 2210-25-5
• Catalog Number: ACM2210255
• Category: Main Products
• Molecular Weight: 113.2
• Molecular Formula: H₂C=CHCONHCH(CH₃)₂
• Synonyms: AKOS 91289;Isopropyl acrylamide;ISOPROPYLACRYLAMIDE(N-);N-ISOPROPYLACRYLAMIDE;NIPAM;2-Propenamide, N-(1-methylethyl)-;Isopropylamid kyseliny akrylove;isopropylamidkyselinyakrylove
• IUPAC Name: N-propan-2-ylprop-2-enamide
• SMILES: CC(C)NC(=O)C=C
• InChI Key: QNILTEGFHQSKFF-UHFFFAOYSA-N
• Boiling Point: 89-92ºC (2 mmHg)
• Melting Point: 64-65°C
• Flash Point: 119.7ºC
• Density: 0.877g/cm³
• Appearance: solid
• EC Number: 218-638-5
• Exact Mass: 113.08400
• Hazard Statements: Irritant
• Safety Description: S26-S36/37/39
• WGK Germany: 3

Case Study

N-iso-Propylacrylamide: Fluorescent Thermo-/pH-Responsive Nanogels for Drug-Delivery Research

Mohsen, R., et al. Journal of Nanomedicine and Nanotechnology 7.2 (2016): 363-372.

Poly(N-isopropylacrylamide) (pNIPAM) is a widely studied thermo-responsive polymer whose hydrophilic-to-hydrophobic transition at a volume phase transition temperature (VPTT) enables temperature-triggered uptake/release behavior. This study reported the design, synthesis, characterization and preliminary biocompatibility testing of a fluorescent, temperature- and pH-responsive nanogel prepared from N-iso-propylacrylamide (NIPAM): poly(N-isopropylacrylamide-co-5% Lucifer Yellow) - abbreviated p(NIPAM-co-5% LY).
Synthesis of Fluorescent Nanoparticles: In a 1L reactor, the initiator potassium persulfate was dissolved in water and heated to 70°C under a nitrogen atmosphere. A pre-mixed aqueous solution containing the monomer N-isopropylacrylamide (NIPAM, 4.75 g), the co-monomer Lucifer Yellow (LY, 0.25 g, constituting 5% by mass of the monomer feed), and the cross-linker N,N'-methylenebisacrylamide was added. The reaction proceeded at 70°C with continuous stirring for 6 hours. Workup: cool to room temperature, dialyze in deionized water for one week (daily changes), centrifuge and freeze-dry the nanogel dispersion.
Key Performance: The produced particles showed reversible volume changes around a volume phase transition temperature (VPTT) ≈ 35 °C, and exhibit favorable cell-viability (>80%) on Hela and Vero cells up to 3 mg/mL (particle dispersions). By contrast, the free NIPAM monomer is substantially more cytotoxic (viability >80% only at ≤0.3 mg/mL; ~10% viability at 3 mg/mL). These data support further exploration of NIPAM-based fluorescent nanogels as thermoresponsive carriers for controlled release applications.

Development of Poly(N-isopropylacrylamide)-Based Kinetic Hydrate Inhibitors via Post-Synthetic Modification

da Silveira, Kelly Cristine, et al. Fuel 188 (2017): 522-529.

A targeted library of poly(N-isopropylacrylamide) (PNIPAM)-based kinetic hydrate inhibitors (KHIs) was generated by post-synthetic modification of a well-defined PNIPAM-co-acrylic acid (PNIPAM-co-AA) copolymer. Because all library members share nearly identical backbone molecular weight, dispersity, end groups and overall composition (base copolymer: 80 mol% NIPAM / 20 mol% acrylic acid; Mn ≈ 11.5 kDa; PDI 1.79), the study could attribute differences in KHI performance to the appended functionalities rather than polymer-size effects. A high-throughput screening protocol showed that select side-group chemistries improve hydrate-inhibition performance, and that post-modification can also tune cloud-point/deposition behaviour - critical parameters for field use in natural-gas transport.
Controlled Synthesis and Library Generation
· Base polymer synthesis: Free-radical copolymerization of NIPAM (60.0 g, 0.53 mol) and acrylic acid (AA, 10.2 g, 0.14 mol) in isopropanol (total 300 mL) initiated with AIBN (1.40 g) at 60 °C, 15 h, under nitrogen. The precipitated polymer was isolated by water reprecipitation into ethyl acetate, hot filtration, vacuum drying (50 °C, 24 h) and lyophilisation; gravimetric yield ≈ 92% (64 g).
· Post-synthetic modification: Aqueous PNIPAM-co-AA (20 w/v%) was activated with EDC/NHS, then reacted with an array of primary amines (cyclic and linear) at defined modification ratios (mol% amine range 1.5-20 mol%). Molar stoichiometry used for each modification was 1 AA : 1 EDC : 1 NHS : 1 amine. Reactions were performed in an ice bath to avoid polymer precipitation; products were lyophilised and used without further purification.