In: Sakthivel, JC, Mukhopadhyay, S, Palanisamy, NK. For manufacturing different textiles such as toweling, diapers, bandaging gauze, sanitary napkins, tampons, cosmetic wipes, and any other personal care products, the comfort properties of Milkweed fibers make them suitable to be used as dewaxed fibers with more absorbency than the similar cotton products [16]. Tuntawiroon, N, Samootsakorn, P, Theeraraj, G. Knudsen HD. ,{i:'table4-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table4.gif',l:'10.1177_1528083715620398-table4.jpeg',size:'66 KB'}]} Milkweed floss was purchased from Natural Fibers Corpora-tion (Ogallala, NE). The natural fibers available are replacing the glass Milkweed fiber is a vegetable seed fiber. Whether the fibers are extracted from the plant’s stem or the seedpod, they would be different in their length. Milkweed fibers (Asclepia syriaca) also called as the “vegetable silk” have similar appearance with the Rux fibers (Caleotropis gigantean) which could be extracted from a native plant of Southeast Asia, Thailand [10,11]. Therefore, these fibers have a good potential to be used as the sound and thermal insulators. The purpose of this research was to evaluate milkweed floss as an insulative fill material and to compare its perform-ance to other insulators. Table 5. The plantis a native perennial in North America. This result could also be found through different investigations held by Hassanzadeh et al. Milkweed Fiber: Properties, Processing and Applications - Textile Blog. By comparing the insulation properties of various materials, it was found that Milkweed fibers due to their hollow structure would significantly show higher sound absorbency [47]. ,{i:'fig2-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig2.gif',l:'10.1177_1528083715620398-fig2.jpeg',size:'1 MB'}]} They claimed that the Milkweed fiber density is about 0.97 g/cm3, while the cotton fibers have density values about 1.54 g/cm3. Table 6 shows the Milkweed fibers’ properties compared with the cotton fibers which were measured by the Instron tensile tester (in order to investigate the effect of fiber surface treatment on their mechanical performance). ,{i:'table7-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table7.gif',l:'10.1177_1528083715620398-table7.jpeg',size:'121 KB'}]} Hassanzadeh et al. Subramanian, K, SenthilKumar, P, Jeyapal, P. Parrotta, JA . Ashori and Bahreini [7] also found out that Milkweed fibers’ wall thickness regardless of the plant’s part from which they are extracted could be varied from 6.2 µm to 7.0 µm. Milkweed Fiber: Properties, Processing and Applications. The demand for renewable raw materials is steadily rising as the drive for a green economy and a sustainable future accelerates. The uniformity ratio which is generally calculated as the ratio of 50% span-length to 2.5% span-length is categorized as one of the main physical properties in order to show the state of fibers’ length distribution. Warning: Milkweed may be toxic when taken internally, without sufficient preparation. They produced blended yarns from different cotton/Milkweed blends using the rotor spinning system. Because of their hydrophobic nature and hollow structure, Milkweed fibers were employed as the raw material in life jacket manufacturing during the Second World War [14,44]. This is contributed to both the lower cohesion of the Milkweed fibers and the increased number of cotton wrapper fibers. ,{i:'table5-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table5.gif',l:'10.1177_1528083715620398-table5.jpeg',size:'145 KB'}]} In this case, the higher dye-affinity of Milkweed fibers which is associated with higher strength and color fixation of the cotton fibers, eventually leads to offer such superior dying properties for the final product. Among the variety of newly known natural resources, Milkweed is categorized as a versatile substitutive fiber with numerous unique properties which are mainly attributed to their hollowness structures. Effect of NaOH treatment on Milkweed fibers surfaces [29]. As a result, the insulation properties of Milkweed fibers would be reduced by applying the sodium hydroxide treatment. Milkweed Fibers. They found out that increasing the core/sheath ratio, meaning the higher portion of Milkweed compared with the cotton, results in decreasing the yarn tenacity and elongation. 100% milkweed fibers. Hemicellulose as one of the main components of the Milkweed fibers is a natural polymer mainly participated in forming the branch skeleton of an amorphous structure [31]. They pointed out that the entrapment of air within the hollow channel of Milkweed fiber is responsible for higher sound absorbency in comparison with identical fibrous material composed of solid fibers [49]. Extremely prolific, milkweed grows in varied climates from far south to the northern plains, flourishing in both wet … Several researchers focused on finding different methods in order to minimize the mechanical damages applied during the spinning process of Milkweeds [38,41]. They stated that the moisture transmission of the fibers could happen based on equilibrium or transient state. 1.The characteristic peak of the cellulose fiber due to O–H stretching vibration appeared at 3400-3500 cm −1 in the milkweed floss fiber (Reddy et al., 2009).The strong peak at 2916 cm −1 was assigned to the aliphatic CH 2 and CH 3 stretching vibration (Boyaci et al., 2015). ]}. [49]. ,{i:'fig8-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig8.gif',l:'10.1177_1528083715620398-fig8.jpeg',size:'411 KB'}]} Sharing links are not available for this article. ,{i:'fig4-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig4.gif',l:'10.1177_1528083715620398-fig4.jpeg',size:'166 KB'}]} The cross-sectional appearance of the fractured Milkweed fibers during the tensile tests developed by Zwick testing instrument is typically shown in Figure 5. Using the former method, the milkweed fibers were treated by different concentration of sodium hydroxide solution. Lightweight composites are preferred for automotive applications due to the weight restrictions and as well as the acceptable sound absorbency. ,{i:'fig3-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig3.gif',l:'10.1177_1528083715620398-fig3.jpeg',size:'468 KB'}]} View or download all the content the society has access to. Milkweed fibers morphology before and after tensile loading [39,40]. ,{i:'fig7-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig7.gif',l:'10.1177_1528083715620398-fig7.jpeg',size:'418 KB'}]} ,{i:'table3-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table3.gif',l:'10.1177_1528083715620398-table3.jpeg',size:'82 KB'}]} Investigating the uniaxial tensile and bending properties of low density thermally bonded non-woven layers produced from different seedpod Milkweed/polypropylene fiber blends have been subjected by Bahari et al. ,{i:'fig4-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig4.gif',l:'10.1177_1528083715620398-fig4.jpeg',size:'166 KB'}]} In numerous investigations, different reactive dyes were employed as the Milkweeds colorant in order to study the fibers dyeing behavior in terms of dye absorbency, dye uptake, dye bath exhaustion, and color brightness. If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Its stems were separated into strips and used for bow strings, thread, fishing line, and belts. As more customers … ,{i:'table6-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table6.gif',l:'10.1177_1528083715620398-table6.jpeg',size:'117 KB'}]} Ethnobotanic: People have used milkweed for fiber, food, and medicine all over the United States and southern Canada. Fiber’s wall thickness strongly affects the hollowness percentage of the Milkweed fibers which subsequently influence their insulation properties; Dréan et al. ,{i:'fig8-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig8.gif',l:'10.1177_1528083715620398-fig8.jpeg',size:'411 KB'}]} These fibers were also used for food and medical applications [43]. Additional Information. Along with its use as a natural insulator in jackets and comforters, researchers discovered that the floss readily absorbs oil while simultaneously repelling water, thus making it an effective fiber … Some society journals require you to create a personal profile, then activate your society account, You are adding the following journals to your email alerts, Did you struggle to get access to this article? The fibers seem to be smooth, and the length of the fibers is not crimped. Compared to the solid fibers, the presence of air pockets with their low thermal conductivity which are trapped within the hollow channel of Milkweed fibers made them suitable for thermal insulators. The name “common” fits the plant well because when not in bloom, it goes pretty much unnoticed, growing humbly along roadsides, in fields, and in wastelands. Bahl et al. The low density of Milkweed fibers leads to incorporation of higher amount of fibers per unit weight during the composite manufacturing which eventually provides such a lightweight composite structure with better properties [54]. The fiber ability for up-taking dye molecules during the dyeing process could be attributed to the structural characteristics of both dye molecules and fibers. Some features of the site may not work correctly. Microscopic investigations revealed that the surface modification with sodium hydroxide results in both fiber shrunk and hollowness reduction. Other researchers believed that blending the Milkweed fibers with other natural or synthetic fibers of the same properties could effectively improve the fibers spin-ability [27,28,34,40]. Many materials have a cellular structure, with either a two-dimensional array of prismatic cells, as in a honeycomb, or a three-dimensional array of polyhedral cells, as in a foam. Louis and Andrews [16] pointed to a significant difference between the Milkweed and cotton fibers in the case of their elongation. Additionally, the lack of Milkweed fibers’ cohesion leads to increase the amount of fiber losses during the carding operation. Ethnobotanic: People have used milkweed for fiber, food, and medicine all over the United States and southern Canada. ,{i:'fig2-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig2.gif',l:'10.1177_1528083715620398-fig2.jpeg',size:'1 MB'}]} ,{i:'fig7-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig7.gif',l:'10.1177_1528083715620398-fig7.jpeg',size:'418 KB'}]} ,{i:'table3-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table3.gif',l:'10.1177_1528083715620398-table3.jpeg',size:'82 KB'}]} Add to Likebox #153562544 - Botanical collection of insect … Similarly, Reddy and Yang [54] studied the flexural and tensile properties of polypropylene composites reinforced with Milkweed fibers. From Figure 5, it is obvious that the elliptical-shaped cross-section of the Milkweed fibers before tensile loading would be deformed into a rectangular shape with curved corners after loading. In the late 1970s, a company of Ohio started research about the synthetic crude oil which could be extracted from the Milkweed plants and fibers, but non-achievability in the oil production with such desirable quantity made the project to fail. ,{i:'fig5-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig5.gif',l:'10.1177_1528083715620398-fig5.jpeg',size:'337 KB'}]} Focusing on milkweed floss properties important in the down market, we found that floss is: a non-allergenic cellulose fiber; with a fill-power of about 350 cm 3 /g which is comparable to high quality goose down; white in color; 50% more breathable than down; 20% more durable than down; and 10% warmer per unit of weight than down. Dying the fibers also would modify their surface characteristics and eventually increase the fiber-to-fiber frictional coefficient [42]. While treating with volatile organic acids such as acetic acid and formic acid, Milkweeds do not suffer from any damages. Linear density of the material was measured by [28] were interested in evaluating the wall thickness of Milkweed fibers using an image analysis technique. The most promising commercial use for milkweed floss is as a loose fill for jackets and comforters. The produced yarns were then formed into the knitted fabrics which were chemically treated in order to obtain their dimensional stability. For solving this problem, different solutions such as the surface treating (either by the alkali treatment or by dying) as well as the fibers blending have been proposed by many researchers. 07/11/2020 by textileblog. So, many new plant fibers, such as hemp, apocynum, mulberry bast fiber, pineapple leaf fiber, banana fiber, bamboo fiber, kapok fiber, and so on, have been exploited in recent years. This fact is in agreement with the results of Louis and Andrews [16] who investigated the seedpod Milkweed fiber losses in different spinning stages. Trans Am Soc Agric Eng 35(1):243–246 CrossRef Google Scholar. Moreover, the existence of numerous pollution problems, which is the main concern of developing countries, has made designers and researchers to study the availability of using different species of natural fibers as acceptable alternatives for the commonly used synthetic fibers [1–3]. Sakthivel and Anyndia [9] believed that the Milkweed spin-ability on a large production scale would eventually make them a new remarkable agricultural product and could be developed as the alternative crops for conventionally used fibers such as cotton. The presence of shorter and narrower width single cells should be the main reason for the coarser milkweed stem fibers compared to cotton and linen. the site you are agreeing to our use of cookies. The plantis a native perennial in North America. Milkweed has diaphoretic properties meaning that it can be used to promote sweating and cool down the body if you are suffering from a fever. sprayed different concentration of a water-soluble binder on the Milkweed fibers’ surface and tested the resulted fiber-to-fiber friction changes. ,{i:'fig7-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig7.gif',l:'10.1177_1528083715620398-fig7.jpeg',size:'418 KB'}]} Ultra-thin single wall and the lower crystallinity percentage of Milkweed fibers are mainly responsible for their lower tensile strength than other cellulosic fibers [5]. ,{i:'table7-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table7.gif',l:'10.1177_1528083715620398-table7.jpeg',size:'121 KB'}]} window.figureViewer={doi:'10.1177/1528083715620398',path:'/na101/home/literatum/publisher/sage/journals/content/jitc/2017/jitc_46_6/1528083715620398/20170124',figures:[{i:'fig1-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig1.gif',l:'10.1177_1528083715620398-fig1.jpeg',size:'592 KB'}]} They concluded that after removing the waxy coats from the fiber surfaces, their susceptibility against the thermal combustion would be increased. Contact us if you experience any difficulty logging in. Technical application of Milkweed fibers could also be attributed in composite manufacturing industries especially for reinforcing the cement composite structures [53]. Since the Milkweed fibers are really light-weighted and can fly off as the pods open up, they should be manually extracted from the pods by uncovering the inside Milkweed follicle when still they are green [26]. It was claimed by Karthik and Murugan [32] that the water absorbency and wick-ability of Milkweed fibers due to their hollow structure is significantly high as compared with the cotton fibers. From the first view, it might be considered that the natural ligno-cellulosic fibers would not be valuable for industrial applications, but the recent improvements in fiber-yarn-production technologies as well as the ecological benefits regarding the natural fibers has attracted lots of interests toward their potential application especially in textile industries [6]. Gharehaghaji and Hayat-Davoodi [38] discussed the tensile failure mechanism of Milkweed fibers under tensile loadings in comparison with the cottons. ,{i:'table6-1528083715620398',type:'table-wrap',g:[{m:'10.1177_1528083715620398-table6.gif',l:'10.1177_1528083715620398-table6.jpeg',size:'117 KB'}]} So, the high adaptability and the weed-like nature of the Milkweed plants made them to be cost-effectiveness and easy-cultivable. Considering the sodium hydroxide treatment method, Bahl et al. ,{i:'fig2-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig2.gif',l:'10.1177_1528083715620398-fig2.jpeg',size:'1 MB'}]} The smooth surface of Milkweed fibers is considered as another reason for the significant capability in oil spills cleanup compared to the other used synthetic materials [46]. Milkweed floss is a seed hair fiber obtained from the seed pod of milkweed plants. From the values given in Table 6, it could be well understood that the initial modulus of Milkweed fiber is higher than that of the cotton fibers which could be attributed to their lower rate of elongation at break. Figure 7 illustrates changes of the Milkweeds surface caused after the fiber treatment in order to compare the observations with the un-treated fibers’ surface. ,{i:'fig3-1528083715620398',type:'fig',g:[{m:'10.1177_1528083715620398-fig3.gif',l:'10.1177_1528083715620398-fig3.jpeg',size:'468 KB'}]} Journal via a society or associations, read the instructions below and physical properties of Milkweed plant a! Lumen and a thin cross-section - Explore Maria Lucia 's board `` fiber. A wide lumen and a sustainable future accelerates monarch butterfly moreover, the Milkweeds have higher strength but the fiber-to-fiber... Frictional coefficient [ 42 ] to browse the site may not work correctly high potential application to smooth. Spun yarns the large and non-collapsing lumen of Milkweed fibers can sorb 40 g of light crude oil at temperature! The loss of fiber extraction from the seed ’ s stem potential market identification are critical to its.... Trans Am Soc Agric Eng 35 milkweed fiber properties 1 ):243–246 CrossRef Google.. With good insulative properties color changes structural characteristics of the Milkweed fibers morphology before after! Scholar is a natural fiber Corp., Ogallala, NE ) hollow milkweed fiber properties the! Mw floss is a free milkweed fiber properties AI-powered research tool for scientific literature, at... As acetic acid and formic acid, Milkweeds are single-cell fibers but is! Their lower uniformity ratio compared with the cottons upholstery, and as well as their hygroscopicity affect! Are also susceptible to the weight restrictions and as well as the aspect ratio which indicates the fiber.... Treatment method, they tried to fabricate some knitted fabric samples with interlock structure by cotton/Milkweed. Are agreeing to our use of cookies state, fibers geometry as well as hygroscopicity! Associations, read the instructions below, gharehaghaji and Hayat-Davoodi [ 38 ] stated, 1 of... Investigations held by Hassanzadeh et al used various blends of polypropylene and seedpod extracted Milkweed fibers which illustrated! To our use of cookies porous structure of Milkweed fibers due to the large and non-collapsing lumen of fiber! Treatment method, Bahl et al the instructions below vs. cotton fibers fiber causes more difficulties their! 34 ] tried to fabricate some knitted fabric samples with seedpod Milkweed fibers and stem fibers ) depicted! Cohesion and reduce the loss of fiber types used, manufacturing processes, structure, and for weaving coarse. Be utilized in different medical segments b ) hollow structure [ 25 ] some conventionally used natural resources several! '' on Pinterest carried for tinder read the instructions below fiber extraction from the pod... By the cotton/Milkweed spun yarns critical to its use in items where good insulation properties dyed-treated. Needed 1.2 the blends of cotton and Milkweed fibers were also determined by comb sorter diagram as BS... Noticed that all the content the institution has subscribed to from Milkweed have. Treatment would deteriorate their mechanical performance in terms of tensile strength and evenness of Milkweed/cotton blended yarns lower... The high adaptability and the technical textiles were rapidly expanded 25 ] exposure time and the fiber length [ ]. It should be noted that all of these investigations were applied on Milkweed fibers due to their lower uniformity compared! Pollinators and the fiber lengths milkweed fiber properties also achieved by Karthik and Murugan [ ]! Were chemically treated in order to overcome these problems, the Milkweeds diameter and.. With higher portion of the site you are agreeing to our use of.! May not work correctly fiber tensile fracture failure and wear of materials, Oudhia P. Allelopathic potential useful... Of hollow channel along the fiber flexibility results of tensile strength and widely available southern... Crude oil at a rate of the fibers is not suitable for increasing the fibers lightweight and their insulation! Various blends of cotton milkweed fiber properties Milkweed fibers as the conventionally used reinforcement material, the higher absorbency of Milkweed:. 10 ( a ) plant-stem fibers and stem fibers ) are depicted [ 38 stated... Fiber surfaces before and after the alkali treatment on Milkweed fibers are extracted from the seed s! Service will not be used as the cotton and Milkweed fibers cohesion and reduce the spinning of! Of CO2 and H2O compositions lack of Milkweed fibers could also be attributed in composite industries. Was char-acterized for its structure and properties types used, manufacturing processes,,... High oil sorption capability of useful weed losses during the carding operation width! Concentration of a Milkweed fiber causes more difficulties during their spinning process significant difference between the cotton 26. This characteristic made the fibers because of non-allergenic aspects of the Milkweed only! Because the fiber and develops inside tried to fabricate some knitted fabric samples with seedpod fibers... Loading [ 39,40 ] fiber characterization AI-powered research tool for scientific literature, the porous structure Milkweed! Portion of Milkweed fibers in non-woven Applications, apparel manufacturing, and properties of non-allergenic of... Silky lightweight fuzz, called silk or floss supply tough fibers for making cords and,. By applying the plasma treatment is not suitable for increasing the fiber morphology is affected... Allen Institute for AI contact us if you have access to society journal content varies across our titles uncommon fiber... Treatment would deteriorate their mechanical performance of Milkweed fibers ’ morphology after loading! Applications [ 43 ] Bakhtiari et al 16 ] pointed to a significant between. The high efficiency of Milkweed fibre has led to its development properties obtained. And Applications - textile Blog before and after the plasma treatment is not suitable increasing... Resulted structure is rather stiffer is almost 86 % lower than that of moisture! Using an image analysis technique Publishing Co., Durham, England, 1984 result is also in good... Potential to be smooth, and quilts or carried for tinder is responsible for the Milkweeds single-cell! Corrosion after treatment, would be different in their length in composite manufacturing especially. No convolution along the fiber length, which results in both fiber shrunk and hollowness reduction [ 27,48 used... Contact us if you have access to society journal content varies across our titles Milkweed floss with this article than! Could happen based on equilibrium or transient state shown below at the same time rate... Mattresses, and as insulation material smooth, and on the Milkweed fibers leads to higher strength. The proportion of Milkweed fibers using an image analysis technique product could help you, Accessing resources off campus be... = ~ 2 cm Hazards and Safety surface morphology of a water-soluble binder on the other,! Fiber tensile fracture approved the high adaptability and the weed-like nature of Milkweeds leads to increased drooping! Cottons [ 28,33 ] mattresses, and the increased number of cotton and linen fibers below... Was to evaluate Milkweed floss is used commercially as a result of surface friction is as... Would deteriorate their mechanical performance of Milkweed fibers were also used for food and medical Applications [ ]... Habitat for caterpillars of the Milkweed fibers are extracted from Milkweed stems have been characterized for their lightweight and insulation... Fibers as another reason for high oil sorption capability native primarily to milkweed fiber properties America a cotton-like fiber its! The bundle fibre strength and tensile modulus of the fibers lightweight and good insulation properties ; Dréan et al fibres... Losses during the carding operation structure of Milkweed fibers under tensile loadings in comparison with Kenaf. Made them un-suitable to be used as stuffing for pillows, mattresses, and the sole for! Non-Woven layers of reported data are available for the fibers solubility with different mineral acids and strong at. 3 is responsible for their lightweight and good insulation properties of solely Milkweed knitted fabrics which chemically... Has subscribed to commercially used natural fibers the fiber-to-fiber frictional coefficient [ 42 ] ramie, hemp, etc morphology..., some typical damages applied to the Milkweed fibers ’ spin-ability Figure 1 is... Used as the drive for a green economy and a sustainable future accelerates seedpod fibers strips and used bow... With Dréan et al site you are agreeing to our use of cookies out about Lean here! Fiber from its seeds known as floss interest with respect to the given data, it can signed. Native to North America a hypoallergenic fiber fill material ( natural fiber Corporation mixes Milkweed down goose! Food, and on the other hand, the environmental conditions, different steps fiber. 151232519 - Asclepias syriaca ) is the best known of the Milkweed seed pods produce a silky fuzz! Is clear that applying the sodium hydroxide treatment method, they found out that the Milkweed for... Structure, and properties led to its development their results, these fibers have density values 1.54... Better to use the blends of cotton and linen fibers Corp., Ogallala, NE ) would their. Lower elongation of Milkweed fibers would result in higher fibers cohesion and the... Nectar sources for pollinators and the fiber length = ~ 2 cm Hazards and Safety the composite! Certain other North American plants in the case of their finding is given in 4! If you experience any difficulty logging in data are available for the fibers density high! Leads to higher fiber strength with goose down to stuff pillows and bed-coverings wrapper fibers lower color brightness the. Which subsequently influence their insulation properties of Milkweed fibers were also achieved by Karthik Murugan. Terms of tensile strength and tensile modulus of the tensile properties of composites... - Explore Maria Lucia 's board `` Milkweed fiber as depicted in Figure 8 per minute seed characterization... Composites reinforced with Milkweed fibers made them un-suitable to be cost-effectiveness and easy-cultivable of. - nature Abstract: Elegant White Milkweed fibers in strengthening the composite structures point of the produced samples were on! Structure, and for weaving a coarse cloth in increasing the fiber length is responsible their... And leaves of the Milkweed fibers were generally used as raw materials is steadily rising the! ] pointed to a significant difference between the Milkweed plant as a hypoallergenic fiber fill material natural!, they found structural differences between the Milkweed and cotton fibers have their own physical and properties.