A COMPOSITE LAMINATE AND ITS USAGE

Abstract

The present invention relates to a laminate for making a molded article comprising: (i) at least one reinforcement Iayer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side, wherein the deployable layer are compactable, expandable or collapsible including Miura-Ori folds, honeycombs, foams or air mesh. The laminate may be used to form a molded article. The molded articles have uses in biomedical, health care and sport protective devices.

Claims

1-30. (canceled)

31. A laminate for making a molded article comprising: (i) at least one reinforcement layer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side.

32. A laminate according to claim 31, wherein the (i) at least one reinforcement layer is a middle layer, the (ii) at least one deployable layer is an inner layer and the (iii) optionally, at least one material comprising at least one non-adhesive side is an external layer.

33. A laminate according to claim 31, wherein the (ii) at least one deployable layer, and the (iii) optionally, at least one material comprising at least one non-adhesive side, are adhered to the surface of the reinforcement layer(s) by the resin matrix, wherein the adhesion is by the cured resin.

34. A laminate according to claim 31, wherein the (iii) optionally, at least one material comprising at least one non-adhesive side is permanently bonded to the reinforcement layer.

35. A laminate according to claim 31, wherein the laminate comprises: (i) a reinforcement layer impregnated with a resin matrix; and (ii) a deployable layer; and (iii) optionally, a material comprising at least one non-adhesive side.

36. A laminate according to claim 31, wherein the (iii) optionally, at least one material comprising at least one non-adhesive side is selected from the group consisting of polyester, nylon, carbon, aramid, and polyolefin or the non-adhesive side has a knitted structure.

37. A laminate according to claim 31, wherein the material of the reinforcement layer is selected from the group consisting of carbon, glass, para-aramid and polymer fibers.

38. A laminate according to claim 31, wherein the resin matrix comprises an epoxy resin, wherein the epoxy resin is a bis-phenol-A epoxy resin.

39. A laminate according to claim 38, wherein the resin matrix additionally comprises a filler; wherein the filler is a nanofiller selected from the group consisting of carbon nanotubes, silica, layered silicates, polyhedral oligomeric silsequioxanes and graphene oxide.

40. A laminate according to claim 31, wherein the deployable layer is a deployable polymer layer comprising polyolefin.

41. A laminate according to claim 31, wherein the deployable layer comprises a pattern of folds, thereby allowing the sheet to be collapsed, wherein the pattern of folds comprises a grid of parallelograms.

42. A laminate according to claim 31, further comprising an anchoring protrusion.

43. A process for making a laminate for making a molded article comprising: (i) at least one reinforcement layer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side, comprising the following: providing a deployable layer; providing a reinforcement layer; impregnating the reinforcement layer with the resin matrix and partially curing the resin matrix; and contacting the reinforcement layer with the deployable layer and hilly curing the resin matrix to form the laminate.

44. A process for making a laminate for making a molded article comprising: (i) at least one reinforcement layer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side, comprising the following: providing a deployable layer; pre-impregnating a reinforcement fiber with a resin matrix and partially curing the resin matrix; weaving the reinforcement fiber to form a reinforcement layer; and contacting the reinforcement layer with the deployable layer and fully curing the resin matrix to form the laminate.

45. The process of claim 44, wherein the reinforcement fiber is selected from the group consisting of glass fiber, carbon fiber, polymeric fiber and any mixture thereof.

46. The process according to claim 43, wherein the reinforcement layer is contacted with the deployment layer to form a multilayer assembly before curing the resin matrix.

47. The process according to claim 46, comprising wrapping the multi-layer assembly around a scaffold before fully curing the resin matrix or comprising removing the scaffold after curing the resin matrix.

48. The process according to claim 43, comprising contacting the cured laminate with at least one material comprising at least one non-adhesive side.

49. The process according to claim 43, comprising anchoring the deployment layer to the reinforcement layer; wherein the anchoring is done using an anchoring protrusion.

50. A molded article obtainable by molding a laminate according to a process for making a laminate for making the molded article comprising: (i) at least one reinforcement layer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side; comprising the following: providing a deployable layer; providing a reinforcement layer; impregnating the reinforcement layer with the resin matrix and partially curing the resin matrix; and contacting the reinforcement layer with the deployable layer and fully curing the resin matrix to form the laminate.

51. A method of using a molded article as a brace for scoliosis, a prosthetic, a sport protector or a safety device, wherein the molded article is obtainable by molding a laminate according to a process for making a laminate for making the molded article comprising: (i) at least one reinforcement layer impregnated with a resin matrix; (ii) at least one deployable layer; and (iii) optionally, at least one material comprising at least one non-adhesive side; comprising the following: providing a deployable layer; providing a reinforcement layer; impregnating the reinforcement layer with the resin matrix and partially curing the resin matrix; and contacting the reinforcement layer with the deployable layer and fully curing the resin matrix to form the laminate.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0102] The accompanying drawings illustrate a disclosed embodiment and serves to explain the principles of the disclosed embodiment. It is to be understood, however, that the drawings are designed for purposes of illustration only, and not as a definition of the limits of the invention.

[0103] FIG. 1 shows an example of a Miura-Ori fold of the deployable layer in one embodiment of the present invention.

[0104] FIG. 2 shows a schematic representation of the preparation steps to produce a composite laminate according to one embodiment of the present invention.

[0105] FIG. 3 is an isometric view of the deployable layer showing breathable holes on the Miura-Ori folds on its top surface and anchoring protrusions on its bottom surface.

[0106] FIG. 4 shows a representation of the top view of the deployable layer comprising Miura-Ori folds, showing the size of each Miura-Ori fold, the size of each breathable hole, the positions of the breathable holes on the Miura-Ori folds and position of each anchoring protrusion. Dimensions shown in the figure are in millimeters.

[0107] FIG. 5a shows a right-view representation of a deployable layer showing the size, shape and thickness of each Miura-Ori fold. Dimensions shown in the figure are in millimeters.

[0108] FIG. 5b shows a front-view representation of a deployable layer showing the thickness of the deployable layer, and the size and shape of each anchoring protrusion. Dimensions shown in the figure are in millimeters.

DETAILED DESCRIPTION OF DRAWINGS

[0109] FIG. 2 shows a schematic representation of the preparation steps to produce a laminate of the present invention.

[0110] Step A: Reinforcement

[0111] The reinforcement fibers (glass fiber/carbon fiber/polymeric fiber) are knitted into the form of a sleeve or sock. The reinforcement fibers may or may not be pre-impregnated with the matrix resin. If the reinforcement fibers have been pre-impregnated with resin, the resin should be non-tacky so that they can be knitted easily. The knitting provides stretchability to the fabric since the reinforcement fibers are not stretchable. This stretchability may be important to allow the material to easily and snugly conform to shapes without the need of external holding forces, such as the use of molds or vacuum bags.

[0112] Step B: Impregnation

[0113] Reinforcements are impregnated with the matrix resin to form a pre-preg. The pre-preg is then B-staged at temperatures of between 30-90 C. in order to allow the resin to become semi-solid. This step is not necessary if the reinforcement fibers have been pre-impregnated with the matrix and B-staged prior to knitting the fibers into a fabric.

[0114] Step C: Wet Pre-Preg Wrapping Over Scaffold

[0115] Inner Miura-Ori layer is adhered to the reinforcement pre-preg layer that is tacky.

[0116] Step D: Air Mesh Casting

[0117] An optional air-mesh may be adhered as the outer layer to provide excellent surface finish and attractive colors and may comprise at least one non-adhesive side. The whole assembly of multiple layers is then and wrapped over the scaffold to take its shape.

[0118] Step E: Oven Curing

[0119] The final multi-layered assembly is cured at elevated temperature, after which the resin will cure to become rigid and the layers will permanently take the shape of the scaffold.

[0120] Step F: Removal of Scaffold

[0121] Depending on the type material used as the scaffold, the scaffold can be removed upon curing of the article.

EXAMPLES

[0122] Non-limiting examples of the invention and a comparative example will be further described in greater detail by reference to specific Examples, which should not be construed as in any way limiting the scope of the invention.

Example 1

Preparation of Pre-Preg Laminate

[0123] The reinforcement fibers (glass fiber/carbon fiber/polymeric fiber) are knitted into the form of a sleeve or sock. The reinforcement fibers may or may not be pre-impregnated with the matrix resin. If the reinforcement fibers have been pre-impregnated with resin, the resin should be non-tacky so that they can be knitted easily. The knitting provides stretchability to the fabric since the reinforcement fibers are not stretchable. This stretchability is important to allow the material to easily and snugly conform to shapes without the need of external holding forces, such as the use of molds or vacuum bags.

[0124] Reinforcements are impregnated with the matrix resin to form a pre-preg. The pre-preg is then B-staged at temperatures of between 30-90 C. in order to allow the resin to become semi-solid. This step is not necessary if the reinforcement fibers have been pre-impregnated with the matrix and B-staged prior to knitting the fibers into a fabric.

Example 2

Preparation of Molded Article

[0125] Inner Miura-Ori deployment layer is adhered to the reinforcement pre-preg layer that is tacky. An optional air-mesh can be adhered as the outer layer to provide excellent surface finish and attractive colors. The whole assembly of multiple layers is wrapped over the scaffold to take its shape.

[0126] The final multi-layered assembly is cured at elevated temperature, after which the resin will cure to become rigid and the layers will permanently take the shape of the scaffold.

[0127] Depending on the type material used as the scaffold, it can be removed upon curing of the article.

Example 3

Measurement of Tensile Properties

[0128] The tensile properties of the reinforcement layer were determined according to ASTM D3039 standards and compared to a conventional polypropylene (PP) material. The mechanical properties of the reinforcement layer are significantly more superior as compared to the other layers in the laminate, thus the mechanical properties of this reinforcement layer was used as a representative of the laminate. ASTM D3039 determines the in-plane tensile properties of polymer matrix composite materials reinforced with high modulus fibers.

[0129] Briefly, a thin flat strip of the material having a constant rectangular cross-section was mounted in the grips of a mechanical testing machine and monotonically loaded in tension while recording load. The ultimate strength of the material was determined from the maximum load carried prior to failure.

[0130] The testing was carried out at room temperature. Crosshead speed was controlled at 2 mm/min.

[0131] The laminate comprises or consists of the following:

TABLE-US-00001 TABLE 1 Laminate Properties Air-mesh Layer Air-mesh provides breathability as well as stretchability. It enhances functionality to the product and also significantly reduces manufacturing time. Reinforcement Layer Provides adequate strength to the product. Knitted fiber loop structures generates open spaces between the yarns and facilitates breathability as well as provide stretchability. Inner (Miura-Ori) Layer Miura-Ori structure allows in-plane airflow through its open channels. The protruded design on the Miura-Ori facilitates the interlocking of inner layer to the reinforcement layer.

[0132] The full laminate thickness is about 4-5 mm The reinforcement layer was cut into test samples with dimensions of 175 mm*25 mm*2 mm (L*W*T).

[0133] The comparative polypropylene material used in this test is as described below in Comparative Example 1.

[0134] The results are summarized in Table 2.

TABLE-US-00002 TABLE 2 Mechanical Property Comparison between laminate of present invention and conventional PP Sheet Modulus Samples (GPa) Strength (MPa) Breathable pre-preg 3.8 32 (course Laminate direction) PP 0.88 23.6

[0135] As shown in Table 2, the laminate of the present invention shows superior properties in terms of tensile properties when compared to conventional PP. The present laminate article possesses a high modulus (3.8 GPa) and a high strength (32 MPa) whereas the PP article shows significantly poorer performance at 0.88 GPa and 23.6 MPa. The knitted structure of the reinforcement fabric is characterized by the direction of interlocking loops. The meandering path of the yarn through the fabric is known as the course direction.

Comparative Example

Comparative Example 1

Preparation of PP (Comparative Example)

[0136] The polypropylene copolymer manufactured by North Sea Plastic was used to mold sheets with a thickness of 3.1 mm The PP sheet was cut into test samples with a dimension of 175 mm*25 mm*2 mm (L*W*T).

INDUSTRIAL APPLICABILITY

[0137] The disclosed laminate allows for the manufacturing of molded articles with improved mechanical strength. Due to the improved mechanical strength, thin molded articles can be made. The laminate can be molded into any desirable shape. Such molded article may have numerous uses for which can be mentioned the use as a brace for scoliosis, a prosthetic, a sport protector or a safety device.

[0138] The disclosed laminate allows for the manufacturing of devices with good ventilation as needed for example in the field of body braces that cover a large body area. The laminates according to the invention may further lead to molded articles wherein all layers are adhered to each other without the need for additional adhesive layer(s). The laminates can be used to make devices which need resistance against wear and tear problems.

[0139] The disclosed laminate may also be used in customizable support structures for construction such as molds for concrete, large claddings, temporary structures/barriers, protective housings for equipment, wearable supports/protectors such as genouillere, elbow support, and leg guard, safety helmets for cycling, skate-boarding, customized furniture and structures for bikes and scooters.

[0140] It will be apparent that various other modifications and adaptations of the invention will be apparent to the person skilled in the art after reading the foregoing disclosure without departing from the spirit and scope of the invention and it is intended that all such modifications and adaptations come within the scope of the appended claims.