公开(公告)号：US20190077056A1

公开(公告)日：2019-03-14

申请号：US16188304

申请日：2018-11-13

Applicant: University of Electronic Science and Technology of China

Inventor： Weizhi Li ,  Yuming Wu ,  Xiaosong Du ,  Jimeng Li ,  Huiling Tai ,  Guangzhong Xie

IPC: B29C41/00 ,  B29C41/46 ,  B29C41/52

Abstract: A one-step solution casting method for preparing a PVDF-based pyroelectric polymer film is provided, which belongs to the technical field of functional material preparation. The method comprises steps of: treating a substrate with a hydrophilic reagent to obtain a hydrophilically-modified substrate, and then casting the organic solution of polyvinylidene fluoride (PVDF) or its copolymer on the hydrophilically-modified substrate. After cured, the as-casted PVDF-based film shows pyroelectricity without undergoing any stretching or poling post-treatment, indicates that the dipoles of the one-step prepared film are aligned. The self-polarization of the prepared film is attributed to a hydrogen bond induced layer-by-layer electrostatic self-assembly growth mechanism. The method is simple, low cost, high efficient, high capability to produce thick and large-area film with smooth morphology and ease to be scalized.

公开(公告)号：US10730226B2

公开(公告)日：2020-08-04

申请号：US15893678

申请日：2018-02-11

Applicant: University of Electronic Science and Technology of China

Inventor： Weizhi Li ,  Jimeng Li ,  Yuming Wu ,  Xiaosong Du ,  Huiling Tai ,  He Yu

IPC: B29C55/04 ,  C08J5/18 ,  B29C41/00 ,  B29C41/02 ,  B29C41/46 ,  B29C55/00 ,  B29L7/00 ,  B29K27/00 ,  B29K105/00

Abstract: A method for preparing a pyroelectric polymer film based on a combined process of solution casting and uniaxial stretching is disclosed. The pyroelectric polymer film is firstly prepared by solution casting, afterwards, the casted film is subjected to uniaxial stretching when the film is in a semi-cured state (wet film). Thus a larger stretching ratio (>10) at a lower temperature (even at room temperature) is realized. Without undergoing a further poling process, the as-stretched film does have a fairly, good pyroelectric performance. Moreover, the surface of the stretched film is smoother and has fewer surface defects.

公开(公告)号：US20180186060A1

公开(公告)日：2018-07-05

申请号：US15893678

申请日：2018-02-11

Applicant: University of Electronic Science and Technology of China

Inventor： Weizhi Li ,  Jimeng Li ,  Yuming Wu ,  Xiaosong Du ,  Huiling Tai ,  He Yu

IPC: B29C55/04 ,  C08J5/18 ,  B29C41/00 ,  B29C41/02 ,  B29C41/46 ,  B29C55/00

CPC classification number: B29C55/04 ,  B29C41/003 ,  B29C41/02 ,  B29C41/46 ,  B29C55/005 ,  B29K2027/16 ,  B29K2105/0073 ,  B29K2995/0003 ,  B29L2007/008 ,  C08J5/18 ,  C08J2327/16 ,  C08J2327/20

Abstract: A method for preparing a pyroelectric polymer film based on a combined process of solution casting and uniaxial stretching is disclosed. The pyroelectric polymer film is firstly prepared by solution casting, afterwards, the casted film is subjected to uniaxial stretching when the film is in a semi-cured state (wet film). Thus a larger stretching ratio (>10) at a lower temperature (even at room temperature) is realized. Without undergoing a further poling process, the as-stretched film does have a fairly good pyroelectric performance. Moreover, the surface of the stretched film is smoother and having less surface defects.

公开(公告)号：US11235496B2

公开(公告)日：2022-02-01

申请号：US16188304

申请日：2018-11-13

Applicant: University of Electronic Science and Technology of China

Inventor： Weizhi Li ,  Yuming Wu ,  Xiaosong Du ,  Jimeng Li ,  Huiling Tai ,  Guangzhong Xie

IPC: B29C41/00 ,  B29C41/46 ,  B29C41/52 ,  B29L7/00 ,  B29K27/00

Abstract: A one-step solution casting method for preparing a PVDF-based pyroelectric polymer film is provided, which belongs to the technical field of functional material preparation. The method comprises steps of: treating a substrate with a hydrophilic reagent to obtain a hydrophilically-modified substrate, and then casting the organic solution of polyvinylidene fluoride (PVDF) or its copolymer on the hydrophilically-modified substrate. After cured, the as-casted PVDF-based film shows pyroelectricity without undergoing any stretching or poling post-treatment, indicates that the dipoles of the one-step prepared film are aligned. The self-polarization of the prepared film is attributed to a hydrogen bond induced layer-by-layer electrostatic self-assembly growth mechanism. The method is simple, low cost, high efficient, high capability to produce thick and large-area film with smooth morphology and ease to be scalized.