Enhancing the Matrix-Fiber Interface with a Surfactant Leads to Improved Performance Properties of 3D Printed Composite Materials Containing Cellulose Nanofibrils.

Cellulose nanofibrils (CNFs) exhibit characteristics that make them a desirable addition to new composite materials. CNFs are usable in a wide variety of applications such as coatings, personal and healthcare products, packaging, and advanced structural materials. They can also help overcome some performance issues with objects 3D printed by stereolithography (SLA) including dimensional instability and poor mechanical properties.

Improving UV Curing in Organosolv Lignin-Containing Photopolymers for Stereolithography by Reduction and Acylation.

Despite recent successes in incorporating lignin into photoactive resins, lignin photo-properties can be detrimental to its application in UV-curable photopolymers, especially in specialized engineered resins for use in stereolithography printing. We report on chemical modification techniques employed to reduce UV absorption by lignin and the resulting mechanical, thermal, and cure properties of these modified lignin materials. Lignin was modified using reduction and acylation reactions and incorporated into a 3D printable resin formulation.

Mechanochemically directed metathesis in group 2 chemistry: calcium amide formation without solvent.

Ball milling CaI2 and [KN(SiMe3)2] in a 1 : 1 ratio without solvent, and then extracting the ground material with toluene, yields the synthetically valuable neutral amide [Ca(N(SiMe3)2)2] in good yield, without the contamination by calciate species that complicates solution metathesis routes. The effects on yield of grinding time, milling frequency, and calcium halide identity are also examined.

Dual-emitting film with cellulose nanocrystal-assisted carbon dots grafted SrAlO, Eu, Dy phosphors for temperature sensing.

In this study, we synthesized a novel dual-emitting fluorescent phosphor from cellulose nanocrystal (CNC)-assisted carbon dots (CDs)-grafted SrAlO, Eu, Dy (SAO) through a facile core-shell process. The CNC-CDs-coated SAO presents excellent scattered dual-emission and improved water resistance without destruction of the SrAlO crystals. The phosphors were then reacted with coupling amino-silane and assembled with nanofibrillated cellulose skeletons to create flexible isotropic films.

Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions.

Background: Lignocellulosic biomass requires either pretreatment and/or fractionation to recover its individual components for further use as intermediate building blocks for producing fuels, chemicals, and products. Numerous ionic liquids (ILs) have been investigated for biomass pretreatment or fractionation due to their ability to activate lignocellulosic biomass, thereby reducing biomass recalcitrance with minimal impact on its structural components. In this work, we studied and compared 1-allyl-3-methylimidazolium formate ([AMIM][HCOO]) to the commonly used 1-ethyl-3-methylimidazolium acetate ([EMIM][CHCOO]) for its potential to activate hybrid poplar biomass and enable high cellulose and hemicellulose enzymatic conversion.

Lignin-Containing Photoactive Resins for 3D Printing by Stereolithography.

Generating compatible and competitive materials that are environmentally sustainable and economically viable is paramount for the success of additive manufacturing using renewable materials. We report the successful application of renewable, modified lignin-containing photopolymer resins in a commercial stereolithography system. Resins were fabricated within operable ranges for viscosity and cure properties, using up to 15% modified lignin by weight.

Sustainable Hydrogels Based on Lignin-Methacrylate Copolymers with Enhanced Water Retention and Tunable Material Properties.

Synthesizing lignin-based copolymers would valorize a major coproduct stream from pulp and paper mills and biorefineries as well as reduce the dependence on petrochemical-based consumer goods. In this study, we used organosolv lignin isolated from hybrid poplar ( Populus trichocarpa × P. deltoides) to generate lignin-containing methacrylate hydrogels.

Relationship between lignocellulosic biomass dissolution and physicochemical properties of ionic liquids composed of 3-methylimidazolium cations and carboxylate anions.

The ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([EMIM]Acetate) has been widely used for biomass processing, i.e., to pretreat, activate, or fractionate lignocellulosic biomass to produce soluble sugars and lignin.

Structural distortions in M[E(SiMe₃)₂]₃ complexes (M = group 15, f-element; E = N, CH): is three a crowd?

The tris(bistrimethylsilylamido) species P[N(SiMe3)2]3 (1) and As[N(SiMe3)2]3 (2) have been prepared through halide metathesis in high yield. Their single crystal X-ray structures, along with that of Sb[N(SiMe3)2]3 (3), complete the series of structurally authenticated group 15 M[N(SiMe3)2]3 complexes (the bismuth analogue (4) has been previously reported). All four complexes possess the expected pyramidal geometries, with progressively longer M-N bond distances from P to Bi but closely similar N-M-N angles (107-104°).

Reaction of platinum(II) diamine and triamine complexes with selenomethionine.

We have reacted [Pt(dien)Cl]Cl, [Pt(en)(D(2)O)(2)](2+), and [Pt(Me(4)en)(D(2)O)(2)](2+) [Me(4)en = N,N,N',N'-tetramethylethylenediamine] with selenomethionine (SeMet). When [Pt(dien)Cl]Cl is reacted with SeMet, [Pt(dien)(SeMet-Se)](2+) is formed; two Se-CH(3) resonances are observed due to the different chiralities at the Se atom upon platination. In a reaction of [Pt(dien)Cl]Cl with an equimolar mixture of SeMet and Met, the SeMet product forms more quickly though a slow equilibrium with approximately equal amounts of both products is reached.

Classical versus bridged allyl ligands in magnesium complexes: the role of solvent.

Magnesium allyl complexes are regularly isolated with classical, sigma-bonded ligands, and this has been thought to be their preferred mode of bonding. Density functional theory calculations confirm that such bonding is the most stable mode when coordinated bases are present, but in their absence, pi-bonded forms are expected to be lower in energy. The isolation of the unsolvated [Mg{C(3)(SiMe(3))(2)H(3)}(2)](2) complex supports this prediction, as it is a dinuclear species in which two allyl ligands bridge the metals and display cation-pi interactions with them.

Solution interaction of potassium and calcium bis(trimethylsilyl)amides; preparation of Ca[N(SiMe3)2]2 from dibenzylcalcium.

Ca[N(SiMe(3))(2)](2) (1) is isolated in nearly quantitative yield from the room temperature reaction of Ca(CH(2)Ph)(2)(THF) and HN(SiMe(3))(2) in toluene. A commonly used preparation of 1 involving the reaction of potassium bis(trimethylsilyl)amide, K[N(SiMe(3))(2)] (2), with CaI(2) can produce material that contains substantial amounts of potassium, probably in the form of a calciate such as K[Ca{N(SiMe(3))(2)}(3)]. The favorable formation of K[Ca{N(SiMe(3))(2)}(3)] from 1 and 2 was confirmed with density functional theory calculations.