Full metadata record
| DC Field | Value | Language |
|---|---|---|
| dc.contributor | School of Fashion and Textiles | en_US |
| dc.contributor.advisor | Hu, Hong (SFT) | en_US |
| dc.contributor.advisor | Fei, Bin (SFT) | en_US |
| dc.creator | Ju, Zixin | - |
| dc.identifier.uri | https://theses.lib.polyu.edu.hk/handle/200/13835 | - |
| dc.language | English | en_US |
| dc.publisher | Hong Kong Polytechnic University | en_US |
| dc.rights | All rights reserved | en_US |
| dc.title | Development of sustainable and comfortable poly(lactic acid) mattress surface fabrics with integrated capacitance sensors for sleep monitoring | en_US |
| dcterms.abstract | Sleep is essential for maintaining health and promoting brain function and immune strength, while insufficient sleep increases the risks of illness and early mortality. Improving sleep quality has become a major research focus, with efforts centered on optimizing environmental factors like mattress comfort and employing advanced technologies such as integrated sensors for behavioral data collection. Among these, mattress surface fabrics are attracting growing attention for their ability to simultaneously enhance the contact environment through improved comfort and enable real-time sleep behavior monitoring via embedded sensing technologies. However, traditional mattress surface fabrics, typically made from commonly used synthetic fibers that lack sustainability or natural fibers that are prone to bacterial growth, raise significant concerns regarding environmental impact and hygiene. Poly(lactic acid) (PLA) emerges as an ideal alternative material due to its renewable origins, biodegradability, antibacterial properties, and excellent mechanical performance. Despite its potential, the application of PLA in mattress surface fabrics remains unexplored. | en_US |
| dcterms.abstract | To address this gap, this study aims to design and fabricate a PLA-based smart mattress surface fabric that combines enhanced comfort with integrated sleep monitoring functionality. The research begins with producing crimped PLA filaments in four linear densities (150D, 450D, 600D, and 900D) using the knit-de-knit technique. Through a comprehensive evaluation of their crimped and tensile properties, optimal heat-setting conditions of 120°C for 90 s were determined, and predictive models for these properties were established. The optimized crimped PLA filaments exhibit excellent crimped and tensile properties, making them highly suitable as inlaid filaments in mattress surface fabrics. | en_US |
| dcterms.abstract | Subsequently, crimped PLA filaments were utilized to produce PLA weft-knitted inlaid fabrics for mattress surface applications. The effects of connection rate, stitching pattern shape, and yarn types on the physical and comfort properties of these fabrics were systematically investigated, along with their durability. The findings reveal that increasing the connection rate enhances fabric air and water vapor permeabilities while reducing thermal insulation and compression energy absorption. Stitching pattern shape also plays a critical role, with triangular patterns promoting air permeability, hexagonal patterns leading to greater thickness loss, and rhombic patterns absorbing more compression energy. Additionally, fabrics made with crimped PLA inlaid filaments exhibit superior comfort properties, reduced thickness loss, and higher compression energy absorption. Compared to PET fabrics, these PLA fabrics display improved water vapor permeability and comparable overall comfort, pilling, and abrasion resistance, highlighting their potential as sustainable materials for mattress applications. | en_US |
| dcterms.abstract | To achieve sensing functionality, this study further integrated conductive yarns into PLA weft-knitted inlaid fabrics, developing a PLA-based textile capacitive pressure sensor (TCPS) through the intarsia knitting technique. The improved TCPS exhibits a sensitivity range of 1.73–0.09 kPa⁻¹ within 0–15 kPa, along with stable capacitive responses under varying compressive pressures (1–15 kPa) and rates (5–20 mm/min). Moreover, it maintains consistent performance even after five washings and 5000 compression cycles, emphasizing its durability. Building on this, a PLA smart mattress surface fabric integrating a 4 × 4 matrix of 16 TCPS units was seamlessly fabricated. Supported by a wireless data acquisition system, this fabric records capacitance changes across each TCPS, enabling real-time monitoring of sleep behaviors such as getting into and out of bed, lying flat, and lying on the side. To analyze the recorded capacitance data, a one-dimensional convolutional neural network (1D-CNN) was developed, achieving 100% accuracy in classifying sleep behaviors and 80–100% accuracy in identifying seven participants. In conclusion, this study successfully develops a sustainable, comfortable, and intelligent PLA-based mattress surface fabric, providing a reliable technical foundation for advanced sleep monitoring applications. | en_US |
| dcterms.extent | xx, 163 pages : color illustrations | en_US |
| dcterms.isPartOf | PolyU Electronic Theses | en_US |
| dcterms.issued | 2025 | en_US |
| dcterms.educationalLevel | Ph.D. | en_US |
| dcterms.educationalLevel | All Doctorate | en_US |
| dcterms.LCSH | Biodegradable plastics | en_US |
| dcterms.LCSH | Polymers | en_US |
| dcterms.LCSH | Textile fabrics -- Technological innovations | en_US |
| dcterms.LCSH | Mattresses | en_US |
| dcterms.LCSH | Biosensors | en_US |
| dcterms.LCSH | Hong Kong Polytechnic University -- Dissertations | en_US |
| dcterms.accessRights | open access | en_US |
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