There is provided a method of coating a substrate comprising applying a first mixture where the first mixture reacts to form covalent bonds to the substrate surface and where the unreacted parts of the first mixture undergo diffusive mixing with a second layer, which is applied on top of the first mixture. This avoids creation of a weak layer, which may otherwise give lower adhesion. The adhesion as well as mechanical properties including the scratch resistance are improved.

There is provided a method of coating a substrate comprising applying a first mixture where the first mixture reacts to form covalent bonds to the substrate surface and where the unreacted parts of the first mixture undergo diffusive mixing with a second layer, which is applied on top of the first mixture. This avoids creation of a weak layer, which may otherwise give lower adhesion. The adhesion as well as mechanical properties including the scratch resistance are improved.

A vehicle bond filler formulation is provided that includes a part A having curable resin and a monomer reactive diluent. A part B storage-separate, cure initiator package contains a free-radical cure initiator. At least one color changing dye adapted to change color upon mixing the part A and the part B and within ±5 minutes of cure of the curable resin to a sandable condition is present in either the part A or a separate part C, a guide coat colorant, or a combination thereof. A process of for repairing a vehicle body is also provided that includes mixing a part A containing the at least one color changing dye with the part B to form an internal guide coat mixture applied to a substrate of the vehicle body in need of repair. The mixture cures causing the color changing dye to the terminal change color within ±5 minutes of cure of the curable resin to a sandable condition.

A vehicle bond filler formulation is provided that includes a part A having curable resin and a monomer reactive diluent. A part B storage-separate, cure initiator package contains a free-radical cure initiator. At least one color changing dye adapted to change color upon mixing the part A and the part B and within ±5 minutes of cure of the curable resin to a sandable condition is present in either the part A or a separate part C, a guide coat colorant, or a combination thereof. A process of for repairing a vehicle body is also provided that includes mixing a part A containing the at least one color changing dye with the part B to form an internal guide coat mixture applied to a substrate of the vehicle body in need of repair. The mixture cures causing the color changing dye to the terminal change color within ±5 minutes of cure of the curable resin to a sandable condition.

A vehicle bond filler formulation is provided that includes a part A having curable resin and a monomer reactive diluent. A part B storage-separate, cure initiator package contains a free-radical cure initiator. At least one color changing dye adapted to change color upon mixing the part A and the part B and within ±5 minutes of cure of the curable resin to a sandable condition is present in either the part A or a separate part C, a guide coat colorant, or a combination thereof. A process of for repairing a vehicle body is also provided that includes mixing a part A containing the at least one color changing dye with the part B to form an internal guide coat mixture applied to a substrate of the vehicle body in need of repair. The mixture cures causing the color changing dye to the terminal change color within ±5 minutes of cure of the curable resin to a sandable condition.

A copolyester, comprising structural units represented by [I], [II], [III] and [IV]. The number of structural units represented by [III] is 1-99% of the number of structural units represented by [I], and the number of structural units represented by [IV] is 0-99% of the number of structural units represented by [I]. Also provided are a preparation method therefor and an application thereof. Because an introduced high-temperature self-crosslinking group and an ion group can improve the melt viscosity and the melt intensity during burning of a copolyester, and effectively enhance the char-forming capability of the copolyester, the copolyester exhibits excellent flame retardance and anti-dripping performance. The preparation process for the copolyester is mature, convenient to operate, and easy to control and apply to industrial production.

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A copolyester, comprising structural units represented by [I], [II], [III] and [IV]. The number of structural units represented by [III] is 1-99% of the number of structural units represented by [I], and the number of structural units represented by [IV] is 0-99% of the number of structural units represented by [I]. Also provided are a preparation method therefor and an application thereof. Because an introduced high-temperature self-crosslinking group and an ion group can improve the melt viscosity and the melt intensity during burning of a copolyester, and effectively enhance the char-forming capability of the copolyester, the copolyester exhibits excellent flame retardance and anti-dripping performance. The preparation process for the copolyester is mature, convenient to operate, and easy to control and apply to industrial production.

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Provided herein are methods, compositions, devices, and systems for the 3D printing of biomedical implants. In particular, methods and systems are provided for 3D printing of biomedical devices (e.g., endovascular stents) using photo-curable biomaterial inks (e.g., or methacrylated poly(diol citrate)).

Provided herein are methods, compositions, devices, and systems for the 3D printing of biomedical implants. In particular, methods and systems are provided for 3D printing of biomedical devices (e.g., endovascular stents) using photo-curable biomaterial inks (e.g., or methacrylated poly(diol citrate)).

The present description provides a Michael Addition curable composition, comprising A) at least one reactive donor capable of providing two or more nucleophilic carbanions; B) at least one reactive acceptor comprising two or more carbon-carbon double bonds; and C) at least one catalyst for catalyzing the Michael Addition crosslinking reaction between the at least one reactive donor and the at least one reactive acceptor. The present description further provides a coating composition containing the composition and a coated article made therefrom.