基于塑化PLA和热塑性粉的可生物降解混合物的热激活形状记忆行为
Valentina Sessini1,2, Valentina Salaris1, Victor Oliver-Cuenca1
1Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC, Calle Juan de la Cierva 3, 28006 Madrid, Spain.
Polymers
|April 27, 2024
概括
研究了可生物降解的聚乳酸 (PLA) 和热塑性粉 (TPS) 的混合物,以确定其形状记忆特性. 使用寡聚乳酸 (OLA) 作为增塑剂实现了最佳性能,这突显了相相兼容性对形状记忆的重要性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 生物材料是一种生物材料.
背景情况:
- 可生物降解的聚合物,如聚乳酸 (PLA) 和热塑性粉 (TPS),对于可持续材料至关重要.
- 塑化剂用于提高PLA的可加工性和性能,但它们对混合物的兼容性和功能性的影响需要进一步研究.
- 形状记忆聚合物 (SMP) 为各种领域的应用提供了先进的功能,包括生物医学工程.
研究的目的:
- 研究不同塑化剂对PLA/TPS混合物的特性和形状记忆行为的影响.
- 评估塑化剂在这些可生物降解混合物中作为加工辅助剂和兼容剂的双重作用.
- 通过调整它们的玻璃过渡温度,探索这些混合物在生物医学应用中的潜力.
主要方法:
- 聚乳酸 (PLA) 和热塑性粉 (TPS) 的化加工与两个不同的可塑剂混合:纯寡合乳酸 (OLA) 和酸功能化OLA (mOLA).
- 准备的混合物的形态,热和机械性质的表征.
- 在特定的温度和变形下评估化加工材料的热激活形状记忆能力.
主要成果:
- 经过OLA塑化的PLA/TPS混合物 (oPLA/TPS) 在45°C和50%的变形下表现出极好的热激活形状记忆能力.
- 在相同的条件下,mOLA塑化PLA/TPS混合物 (moPLA/TPS) 没有显示形状记忆行为.
- 形状记忆性能的差异归因于形态变化和mOLA塑化混合物中不同相的丧失.
结论:
- 在PLA/TPS混合物中实现有效的形状记忆行为需要在增塑剂和兼容剂功能之间保持谨慎的平衡.
- 存在两个明确的阶段 (固定阶段和切换阶段) 对于形状记忆响应至关重要.
- 由于其可调性特性和形状记忆特性,OLA塑化混合物显示出生物医学应用的潜力.
相关概念视频
Plastic Behavior
196
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
196
Polymer Classification: Stereospecificity
2.4K
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
2.4K
Plastic Deformations
129
Plastic deformation represents a fundamental concept in materials science, which explains the irreversible change in the shape of a material when it experiences stress beyond its elastic capability. This phenomenon is important in structural engineering, especially in designing and analyzing cantilever beams—structures that are securely fixed at one end and bear loads at the opposite end. When these beams are subjected to loads within their elastic range, they will return to their...
129
Polymer Classification: Architecture
2.7K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
2.7K
Types of Step-Growth Polymers: Polyesters
2.2K
The introduction of polyesters has brought major development to the textile industry. The wrinkle-free behavior of polyester blends has eliminated the need for starching and ironing clothes.
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the...
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the...
2.2K
Plasticity
2.1K
Plasticity is the property where an object loses its elasticity and undergoes irreversible deformation, even after the deformation forces are eliminated. If a material deforms irreversibly without increasing stress or load, then this is called ideal plasticity. For example, when a force is applied to an aluminum rod, it changes its shape, but it does not return to its original shape once the force is removed. Plastic deformation or ductility is thus a permanent deformation or change in the...
2.1K


