Limits...
Multi-shape active composites by 3D printing of digital shape memory polymers.

Wu J, Yuan C, Ding Z, Isakov M, Mao Y, Wang T, Dunn ML, Qi HJ - Sci Rep (2016)

Bottom Line: We develop a theoretical model to predict the deformation behavior for better understanding the phenomena and aiding the design.We also design and print several flat 2D structures that can be programmed to fold and open themselves when subjected to heat.With the advantages of an easy fabrication process and the controllable multi-shape memory effect, the printed SMP composites have a great potential in 4D printing applications.

View Article: PubMed Central - PubMed

Affiliation: The George Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.

ABSTRACT
Recent research using 3D printing to create active structures has added an exciting new dimension to 3D printing technology. After being printed, these active, often composite, materials can change their shape over time; this has been termed as 4D printing. In this paper, we demonstrate the design and manufacture of active composites that can take multiple shapes, depending on the environmental temperature. This is achieved by 3D printing layered composite structures with multiple families of shape memory polymer (SMP) fibers - digital SMPs - with different glass transition temperatures (Tg) to control the transformation of the structure. After a simple single-step thermomechanical programming process, the fiber families can be sequentially activated to bend when the temperature is increased. By tuning the volume fraction of the fibers, bending deformation can be controlled. We develop a theoretical model to predict the deformation behavior for better understanding the phenomena and aiding the design. We also design and print several flat 2D structures that can be programmed to fold and open themselves when subjected to heat. With the advantages of an easy fabrication process and the controllable multi-shape memory effect, the printed SMP composites have a great potential in 4D printing applications.

No MeSH data available.


Related in: MedlinePlus

Schematics of the printed SMP composite design.(a) The design of the two layer SMP composite strips and (b) the characterization of the design. The purple color represents the fiber with higher Tg and the green color represents the fiber with lower Tg. (c) The typical programming steps for SMPs and desired response.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4829848&req=5

f1: Schematics of the printed SMP composite design.(a) The design of the two layer SMP composite strips and (b) the characterization of the design. The purple color represents the fiber with higher Tg and the green color represents the fiber with lower Tg. (c) The typical programming steps for SMPs and desired response.

Mentions: The composites in this study consist of three materials with different glass transition temperatures (Tgs) and are part of the material library of the multi-material 3D printer (Objet260 Connex, Stratasys Inc, Edina, MN, USA). Figure 1a shows the design of a two-layer composite. The matrix is TangoBlack+, which has the lowest Tg (~2 °C) of the three materials. Two families of digital SMP fibers with different Tgs are embedded in the two layers, respectively, with prescribed volume fractions. The fibers (fiber 1: DM8530, Tg~57 °C; fiber 2: DM9895, Tg~38 °C,) have shape memory effects in the temperature range between ~20 °C and ~70 °C. The dimensions of the design are annotated in Fig. 1b.


Multi-shape active composites by 3D printing of digital shape memory polymers.

Wu J, Yuan C, Ding Z, Isakov M, Mao Y, Wang T, Dunn ML, Qi HJ - Sci Rep (2016)

Schematics of the printed SMP composite design.(a) The design of the two layer SMP composite strips and (b) the characterization of the design. The purple color represents the fiber with higher Tg and the green color represents the fiber with lower Tg. (c) The typical programming steps for SMPs and desired response.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4829848&req=5

f1: Schematics of the printed SMP composite design.(a) The design of the two layer SMP composite strips and (b) the characterization of the design. The purple color represents the fiber with higher Tg and the green color represents the fiber with lower Tg. (c) The typical programming steps for SMPs and desired response.
Mentions: The composites in this study consist of three materials with different glass transition temperatures (Tgs) and are part of the material library of the multi-material 3D printer (Objet260 Connex, Stratasys Inc, Edina, MN, USA). Figure 1a shows the design of a two-layer composite. The matrix is TangoBlack+, which has the lowest Tg (~2 °C) of the three materials. Two families of digital SMP fibers with different Tgs are embedded in the two layers, respectively, with prescribed volume fractions. The fibers (fiber 1: DM8530, Tg~57 °C; fiber 2: DM9895, Tg~38 °C,) have shape memory effects in the temperature range between ~20 °C and ~70 °C. The dimensions of the design are annotated in Fig. 1b.

Bottom Line: We develop a theoretical model to predict the deformation behavior for better understanding the phenomena and aiding the design.We also design and print several flat 2D structures that can be programmed to fold and open themselves when subjected to heat.With the advantages of an easy fabrication process and the controllable multi-shape memory effect, the printed SMP composites have a great potential in 4D printing applications.

View Article: PubMed Central - PubMed

Affiliation: The George Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.

ABSTRACT
Recent research using 3D printing to create active structures has added an exciting new dimension to 3D printing technology. After being printed, these active, often composite, materials can change their shape over time; this has been termed as 4D printing. In this paper, we demonstrate the design and manufacture of active composites that can take multiple shapes, depending on the environmental temperature. This is achieved by 3D printing layered composite structures with multiple families of shape memory polymer (SMP) fibers - digital SMPs - with different glass transition temperatures (Tg) to control the transformation of the structure. After a simple single-step thermomechanical programming process, the fiber families can be sequentially activated to bend when the temperature is increased. By tuning the volume fraction of the fibers, bending deformation can be controlled. We develop a theoretical model to predict the deformation behavior for better understanding the phenomena and aiding the design. We also design and print several flat 2D structures that can be programmed to fold and open themselves when subjected to heat. With the advantages of an easy fabrication process and the controllable multi-shape memory effect, the printed SMP composites have a great potential in 4D printing applications.

No MeSH data available.


Related in: MedlinePlus